SUSREF Sustainable Refurbishment of Building Facades and ... - VTT

SUSREF Sustainable Refurbishment of Building Facades and External Walls 7th framework programme

FINAL

Theme Environment (including climate change)

1.11.2011

Small or medium scale research project Grant Agreement no. 226858

Deliverable: 4.1 Title: Partner-specific product concepts - Description Authors: VTT: Sirje Vares, Sakari Pulakka, Ruut Peuhkuri, Tarja Häkkinen, Anne Tolman VAHANEN: Marja-Liisa Honkanen, Anne-Maria Vierinen EKK: Andres Järvan, Herki Liivrand CU: Kruti Gandhi SGG: Frances Voelcker TECNALIA: Amai Uriarte REPAIR: Elias Hontoria ONEKA: Aitor Epelde TOBB: Runar Skippervik SINTEF: Anna Svensson

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SUSREF Sustainable Refurbishment of Building Facades and External Walls

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List of contents 1 2

3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

Introduction ................................................................................................................... 3 Methodology ................................................................................................................. 6 2.1 Introduction .......................................................................................................... 6 2.2 Building physical assessment .............................................................................. 9 2.3 Life cycle assessment and life cycle costing ...................................................... 11 Concept number 1 by VAHANEN – B1 Brick wall with ventilation gap and vacuum insulated panel............................................................................................................ 13 Concept number 2 by VAHANEN – C1 Re-SOLAR..................................................... 23 Concept number 3 by VAHANEN – T1a. ETICS applied to sandwich element ............ 38 Name of the concept – T1b. ETICS applied to sandwich element internal layer with smooth element surface .............................................................................................. 50 Name of the concept – T1c. ETICS applied to insulated panel RUS ........................... 63 Name of the concept – T1d. ETICS applied to solid panel RUS .................................. 80 NAME OF THE CONCEPT – EKK1 - Filling brick wall cavities with carbamide resin foam............................................................................................................................ 98 Name of the concept – EKK2 - Thermo-reflective multi-foil outer insulation of brick wall with controllable ventilation air gap before insulation................................................. 120 Name of the concept – Exterior refurbishment of wooden frame walls - with a flex system board insulation ............................................................................................ 134 Concept number 1 by ONEKA – Transparent insulation............................................ 151 Concept number 1 by SGG – SGG 1: External insulation of solid rubble stone wall with vapour-open natural insulation material and ventilated timber cladding ............. 166 Concept number 2 by SGG – SGG 2: External insulation of solid rubble stone wall with semi-vapour-open mineral wool insulation material and acrylic render............... 178 Concept number 3 by SGG – SGG 3: External insulation of solid rubble stone wall with expanded polystyrene insulation material and acrylic render ............................ 191 Concept number 4 by SGG – SGG 4: External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding ........................................................ 205 Concept number 5 by SGG – SGG 5: Internal insulation vapour-open of solid rubble stone wall with lime-sand pointing outside................................................................. 218 Summarising remarks on the concepts ..................................................................... 229 Summary .................................................................................................................. 232


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Introduction

This report is the Deliverable 4.1 of WP 4 of the Sustainable Refurbishment of Exterior Walls (SUSREF) project. The overall objectives of SUSREF are to identify the needs to refurbish building envelops in the EU and in neighbouring areas; to understand the meaning of these needs in terms of environmental impacts and in terms of economic impact and business potential; to develop assessment methods and technologies for the refurbishment of building facades and external walls in order to ensure good functional performance of solutions; to analyse different technologies from the view point of building performance and environmental and economical impacts; to deliver sets of relevant performance specifications for sustainable refurbishment; to develop sustainable refurbishment concepts; to disseminate the results for a) building industry, b) standardisation bodies, and c) policymakers and authorities in terms of technological knowledge, guidelines and recommendations. The main aim of WP 4 is the development and description of product concepts for sustainable refurbishment of external walls. The target of the project is to develop both generic refurbishment concepts and specific concepts considering the specific interests and needs of the SME partners of the project. The generic refurbishment cases consider five different technologies: External insulation (E) (Case E1 – insulation fixed without air gap, Case E2 – insulation fixed with air gap and wind protection), Internal insulation (I), Cavity wall insulation (C), and Replacing renovation (R) (old outer layer removed and new layer with additional insulation installed). Existing wall types considered are as follows: Solid wall (brick, natural stone) Sandwich element (concrete panel + concrete panel) Load bearing wood structure (wooden frame) Load bearing cavity without insulation (brick + concrete block) Insulated load bearing cavity (concrete block + concrete block) Non-load bearing cavity (hollow brick + perforated brick) Non-lead bearing concrete block without insulation (hollow brick + concrete block) The generic refurbishment concepts consider different buildings (Small houses, Terraced houses and Multi-storey buildings) and different climatic zones (Cfb, Cfbw, Csa, Dfb, Dfc)1. The generic refurbishment concepts will be described in D4.2 of the project. This report introduces the specific concepts developed by the SME partners of the project together with the research partners. This report describes the concepts developed by Vahanen Oy (VAHANEN) Repair Estructuras S.L. (REPAIR) Oneka Architectura S.L, (ONEKA) Sustainable Gwynedd Gynaladwy Cyf (SGG) Ehituskonstrueerimise ja Katsetuste OU (EKK) and Trondheim og omegn boligbyggelag (TOBB). 1

SUSREF D2.1 System based approach for external walls technologies and comprehensive analysis


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The basic development of the concepts was done by the SME partners and the role of research partners was to carry out life cycle and assessments for the concepts and to support in the overall performance assessment of the concepts. These concepts are targeted for practical use, and the work was based on the understanding the specific challenges faced by the SUSREF SME partners in the development of new sustainable concepts for the refurbishment of facades and external walls. The focus of VAHANEN, REPAIR, SGG, TOBB and EKK was to develop concepts which have good building physical behaviour, make use of new insulating materials options, and offer excellent energy-efficiency considering the varying climatic conditions. ONEKA focused on high-quality aesthetic solutions which provide good indoor environment and comfort and at the same time good energy-efficiency considering the South European climatic conditions. At the same time, the SMEs used their own experience in order to consider the market potentials. The concepts together with assessment results are presented in Chapters 3 - 7. All concepts are described with help of the following outline: Name of the concept Application Market potential Reasoning Known problems related to refurbishment method Cross section figure of the existing external wall Cross section figure of the refurbishment concept Summary of the materials layers and thicknesses Description of working methods Buildability Information about performance values needed in assessment Durability and hygrothermal behaviour Impact on energy demand for heating Impact on energy demand for cooling Impact on renewable energy use potential Impact on daylight Environmental impact of manufacture Impact on life cycle costs Indoor air quality and acoustics Impact on structural stability Fire safety Aesthetic quality Effect on cultural heritage Disturbance to the tenants and to the site Need for care and maintenance


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There where several questions and refurbishment issues that were highlighted by the industrial partners of the project in the beginning of the work. One of the main questions is to what extent it is economical and ecological to improve the insulation capacity of the building envelope when refurbishing existing buildings. Especially the issue arises when estimating the life-span that can be achieved with different technologies. In each case we should be able to optimize the total energy consumption during the lifespan taking into account the embodied energy in the installation stage and the energy consumption during the life-span. Improving the insulation capacity and the air-tightness of the building envelope reflects the indoor air quality. It is important to study the consequences and how to balance and optimize the effects with the HVAC systems (heating, air-conditioning, ventilation) so that good indoor-air quality can be achieved with optimal ecological impact Especially in the Middle and Southern European climatic conditions it would be useful to maximize the use of external energy sources by using intelligent envelope structures in refurbishment projects and optimize the energy absorption to the building envelope. The present U-value calculations do not take into account the external energy sources as means of reducing the need for heating. Important questions include that how refurbishment projects can reduce the heat absorption during the warm season to the building envelope thus reducing the need for air-conditioning; would it be better in some cases to maximize the heat absorption and store it in the massive structures; would it be possible to use the absorbed energy as an energy source for heating and during the warm season for air-conditioning. From the view point of the industrial partners it is also very important to take into account the refurbishment needs and potentials in neighbouring countries outside the EU. The objective of the work was to identify concepts that could be adapted especially in the Russian market. One specific area of problems concerns massive stone walls. The early 20th century buildings in Europe are mainly built using massive stone or brick external walls. These buildings are often of historical value which prevents the building owner or manager from using refurbishment methods that alter the aesthetics of the buildings or using materials that are not compatible with the building's architecture. In this kind of building the prevailing refurbishment methods may cause severe indoor air problems in some climatic conditions but on the other hand may be suitable in other climatic regions. Especially in the former soviet countries these buildings form a real challenge in reducing the energy consumption of real estate. We need a very thorough understanding of the complexity of these structures and fieldtesting and monitoring. In the former soviet countries massive external walls were used as late as the 90´s. These buildings are numerous and often have severe problems with the indoor air quality. This also applies to Estonia and other Baltic countries. Also for example in NW Wales there is a great number of "hard-to- heat" property, both domestic and non-domestic, in that the buildings have solid stone walls 600-800mm thick, no cavities to insulate, ceilings following the underside of the roof, no roof space to insulate, no mains gas outside the few major towns, narrow roads so difficult to get bulk delivery of other fuels. There are also restrictions on fitting double glazing or adding external insulation or draught lobbies to buildings that are listed in Conservation Areas, additionally room sizes in the smaller dwellings prevent insulating significantly inside. Current domestic energy calculation programmes do not take into account the very long time lags inherent in thermal response with such thick walls, which may help or hinder energy performance.


2 2.1

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Methodology Introduction

The product concept development made use of the systemized approach developed in WP 2 (D2.2 Guidelines for the use of building physical modelling methods and tools in the development of sustainable refurbishment technologies for external walls), WP 3 (D3.2 Energy and Thermal Behaviour of building types) and WP 5 (D5.1 Environmental and overall sustainability aspects of external wall refurbishments) and 3 and 5 and the recommended and developed models of assessment. The project did expert assessment, simulations and smaller scale test for the refurbishment concepts developed by the project partners. Finally, the simulation results were verified and confirmed with help of full scale and field tests for selected concepts. field test were made for the selected concepts of SGG and full scale test for the selected concepts of VAHANEN. These results will be later attached to this report when the test will be finalized. The project outlined a framework according to which the sustainability of alternative concepts was assessed. The framework includes 15 sustainability aspects, which are as follows: Durability Need for care and maintenance Indoor air quality and acoustics Impact on energy demand for heating Impact on energy demand for cooling Impact on renewable energy use potential (use of solar panels etc.) Environmental impact Life cycle costs Aesthetic quality Effect on cultural heritage Structural stability Fire safety Buildability Disturbance to the tenants and to the site Impact on daylight The assessment methods were originally introduced in D5.1 as shown in Table 1.


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Table 1 - Assessment criteria Durability and service life Durability and service life will be assessed on the bases of expert knowledge of the partners concerning the age behaviour and deterioration of material and products under scrutiny in relevant outdoor and indoor conditions. The building physical behaviour and risks for deterioration because of moisture related problems like corrosion and mould growth will be analysed with help of building physical simulation. different simulation tools will be used: For constructions and solutions consisting of just homogenous layers, 1D heat and moisture calculations tools (e.g. WUFI-Pro, Match). Ventilated cavities can be studied simplified with these tools, too. For constructions containing inhomogeneous layers, e.g. fastenings, and ventilation cavities, 2D heat and moisture calculations tools (e.g. WUFI2D, DELPHIN) should be used. 3D effects must be taken into account by qualified modification of the model, together with a possible 3D thermal calculation. Generally, 1D tools are sufficient for most of the analysis with skilled expert use. The computation in 2D is usually time-consuming and the detailed information from a 2 or 3D calculation may be overruled by other uncertainties. For qualitative assessment also 2D heat transmission tools can be used for optimisation of the thermal bridges and assessment of the critical temperatures for e.g. mould risk (HEAT2, THERM) Also full scale laboratory tests will be done for selected refurbishment concepts. The assessment will also make use of methods and tools developed earlier for service life estimation. These tools include the ENNUS tools developed at VTT. ENNUS®-tools has been developed for the service life assessment of building structures in compliance with ISO 15686-1. The tools help designers to determine parameters that affect the service life of the structure under scrutiny. The considered parameters include materials quality, structural design, work execution, outdoor and indoor conditions, use conditions, and care and maintenance level. The method is known as the factor method, and service life is obtained by multiplying the reference service life by these factors. VTT has developed ENNUS® tools 2 for concrete outdoor walls and balconies, steel facades and roofings and for wooden outdoor walls. (Service life assessment with help of ENNUS tools was not done for partner specific concepts). Need for care and maintenance The need for care and maintenance will be assessed and explained with help of expert knowledge of the partners concerning the service life behaviour of product in different outdoor and indoor conditions and typical use conditions. The measures which will be considered include issues like needs for periodic inspections and surveys in order to avoid progress of initial deterioration paintings, coatings and other surface treatments renewals of components necessary and laborious cleaning. Indoor air quality and acoustics The indoor environment parameters are outlined as follows: 1) Thermal environment 2) Air Quality 2

http://virtual.vtt.fi/virtual/environ/ennus_e.html


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(Ventilation, Pollution sources - materials, Dampness and mold, NO2, CO, Ozone, Particles (PM 2,5) 3) Noise from outside and from technical equipment 4) Radiation (Radon). Indoor environmental factors are classified as good, normal or bad. For the factors treated in EN 15251 class I corresponds to good, class II normal and class III and IV as bad. Criteria for thermal environment, ventilation /air quality, dampness and mould, noise and radon are given. Guidance on methods and interpretation of user satisfaction is given. No indoor environment tests will be carried out. The effect of alternative refurbishment concepts on the reduction of risk for moisture related problems like corrosion and mould growth and thus for impaired air quality will be assessed with help of building physical simulations (see the list within the box Durability and service life). The guidelines for the use of building physical modelling methods and tools in the development of sustainable refurbishment technologies for external walls are developed in WP 2 and published in D 2.2. The acoustical quality will be assessed in terms of air sound insulation factor (R'w, dB between building spaces). However, this research will not make sound insulation testing. Impact on energy demand for heating and Impact on energy demand for cooling The impact on energy demand for heating will be assessed on the bases of target U-values and on the bases of whole building energy consumption calculations. These calculations are done according to the guidelines developed in WP 3 (especially D3.5). Simple building energy calculations are based on calculating the heat losses and gains and the resulting energy need. Building energy simulations, in addition, take account the dynamic effects of e.g. thermal mass of the building and may in some cases lead to less energy need than the simple calculation. The alternative solutions will be simulated by means of simulation tools, such as EnergyPlus or TRNSYS. Some cases will be analysed in different climates with help of whole building hygrothermal models (e.g. WUFI+ or IDA ICE). (Building level calculation were not carried out for the partner specific concepts) Impact on renewable energy use potential (use of solar panels etc.) Impact on renewable energy use potential (for example the use of solar panels) will be assessed as expert assessments within the project research group. Environmental impact The environmental impact from manufacture and maintenance will be assessed on the basis of LCA as explained in D5.1. Life cycle costs Life cycle costs will be assessed by using the LCC method. The economical assessment covers only extra costs caused and energy cost to be saved by sustainable refurbishment compared with necessary refurbishment of facades. Possible improving in tightness and basic adjustment of heating system has been included in basic refurbishment. Economic assessment is based on the calculation of life cycle cost according to ISO 15686-5 Life Cycle Costing (LCC)3. LCC is a technique for estimating the cost of whole buildings, systems and/or building components and materials, and used for monitoring the occurred throughout the lifecycle. The results are presented in terms of net present values. This is calculated by summing up the activated costs in different years for present with present unit costs (without discount rate). The energy costs were calculated considering the realistic increase of costs. The cost information does not cover maintenance cost because they are don’t schematic caused by chosen technical solutions caused by earlier maintenance works, circumstances etc. 3

ISO 15686-5 Life Cycle Costing.


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Aesthetic quality and Effect on cultural heritage The aesthetic quality and the effect on cultural heritage of the alternatives will be assessed with help of architecture panels. These panels will be invited to assess, discuss and present improvement possibilities for the selected number of alternative refurbishment concepts. The target of these panels will be to identify the key criteria with regard to the effects on cultural heritage. Structural stability and Fire safety The structural stability and fire safety of the alternative refurbishment concepts will be assessed against relevant standards and regulations. However, this research will not carry out mechanical or fire testing of the concepts. Buildability Disturbance to the tenants and to the site Impact on daylight Buildability, Disturbance to the tenants and to the site and Impact on daylight will be assessed as expert assessments within the project research group.

2.2

Building physical assessment

Building physical assessments were carried out at VTT and at CU. The methodologies used are described in the following: The criteria and method developed in D2.2 for the building physical assessment were used and applied in assessing refurbishment concepts. All the concepts were modelled with a hygrothermal simulation tool Wufi Pro 5.0. Simulation has been done for four years and 4th year has been used for the assessment. With the help of the output result for temperature, relative humidity and moisture, a set of performance key values were determined for the critical parts of the constructions. The criteria can be summarized as below: For refurbishment concept with external insulation: Thermal performance of the envelope: reduction of the heat losses through the envelope by adding external insulation and minimising thermal bridges Moisture performance of the envelope: ensuring drying capacity and avoiding condensation by choosing the right materials in right layers Durability of the constructions: reduction of the risk for mould and decay by right choice of materials and ensuring the good moisture performance of the envelope Indoor air quality and comfort: ensuring thermal symmetry, no draft and control of humidity by ensuring good thermal and moisture performance of the envelope.


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For refurbishment concept SGG 3 (internal insulation): This concept has been recommended for plas trion as the building external appearance of a pointed masonry wall need to be retained for aesthetic and/or historical reasons, therefore insulation must be installed internally. A vapour-open system is usually recommended because an internal vapour barrier is very hard to install correctly in an existing structure. With a vapour barrier there is a high risk of trapping moisture within the masonry, causing corrosion or rot in any embedded steel or timber beams, floor joists, lintels, wall plates etc. This system is designed to absorb fluctuations of humidity and release the excess when the peak of humidity has passed. However, the thermal properties for the Calsitherm has been provided by the supplier, therefore some of the hygric properties are missing and simulation has been done on the properties available. Also the owner of the property is a contractor himself and is very keen in using Calsitherm for his house. Thermal performance of the envelope: reduction of the heat losses through the envelope by adding internal insulation and minimising thermal bridges Moisture performance of the envelope: The concept does not perform better after refurbishment in terms of its drying potential and condensation on exterior surface of the wall and also behind the interior plaster. Moisture performance is poor after refurbishment for this concept Durability of the constructions: No reduction of the risk for mould and decay in fact it has increases the risk affecting the moisture performance of the envelope For refurbishment concept SGG 5 (Sheltered opaque): The method of sheltering the wall has been recommended because it removes wind and rain from the external face of the stonework. It reduces air movement across the face of the wall and into gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm. It will benefit from solar gain that can reach the massive stone wall through the relatively still air in the cavity. Thermal performance of the envelope: little reduction of the heat losses through the envelope by adding external sheltered but no insulation Moisture performance of the envelope: The concept performs better after refurbishment in terms of its drying potential and the risk for condensation on the exterior surface of the wall because of external sheltering. Durability of the constructions: There is a reduction of the risk for mould and decay on external surface, however the mould growth risk behind the corrugated sheet and behind air gap is higher after refurbishment.


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Table 2- Summary of the performance criteria for hygrothermal assessment that are recommended to be used in this project. Criteria

Description

Symbol

Unit

Thermal performance

Heat transfer coefficient of external surface

-

W/(m 2K)

Heat transfer coefficient of internal surface

-

W/(m 2K)

Thermal bridging Transmission co efficient Moisture performance

Annual moisture accumulation

fsi u-value w

W/(m 2K) kg/year

Time of wetness (TOW) Risk for frost damage

TOW

h

TOW

h

TOW

h

Tsi

C

T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Indoor climate

Lowest indoor surface temperature

. 2.3

Life cycle assessment and life cycle costing

Environmental impact and life cycle costs were assessed for 17 refurbishment concepts proposed by the SME partners of the SUSREF project. The assessment considered residential buildings and different refurbishment options; existing building type, level of insulation and building location, insulation type used in refurbishment concept, insulation thickness, and local energy type for heating. Environmental impact assessment focused on the impact of non-renewable energy (energy transmission through the wall and energy consumption of refurbishment materials), non-renewable raw materials (from energy production and refurbishment materials) and especially released greenhouse gases and thus carbon footprint. Main parameters for the LCA and LCC calculations were: U-values for existing walls Target U-values Thermal conductivity for used materials Heating degree days Basic renovation cost


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Extra renovation cost Heating cost Environmental loads for materials used Environmental loads for energy types LCA is made according to the next assumptions: life span is 20 year, Pre-defined cites (with specific heating degree days) represent the climatic zones, Main heating energy types are gas (for central and eastern Europe), district heat (Finland), electricity (Nordel), For existing wall no construction materials is considered only impact from heating is calculated, Impact from heating is calculated as the heat flux through the wall. For energy calculations heating degree days for different location, based on +18oC, have been used, Life cycle assessment for material and energy types bases to the general information about their production In some refurbishment cases, with new and advanced materials, life cycle assessment results were not known and thus not included to the energy-, raw-material- and carbon footprint calculation. In these cases result contains only LCA from heat flux through the wall. The assessment method is described in detail in D3.5 (Assessment of refurbishment concepts of concrete sandwich elements and windows in Finland) of SUSREF.


3

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Concept number 1 by VAHANEN – B1 Brick wall with ventilation gap and vacuum insulated panel

This concept has been developed for buildings constructed during the era ca. from 1950 to 1970 when brick was a major material in facades. By then mineral wool was the popular insulation material. Solid brick walls usually have good durability; the material is robust and hardly needs maintenance for a lengthy period. However, bricks are vulnerable to some freeze-thaw phenomena, if the brick has fault in frost resistance (i.e. lacking protective pore structure or lacking strength). Often the visible damage occurs near spouts. Furthermore, water may soak the brick and underlying thermal insulation materials causing notable loss of thermal insulation capacity. Present day brick materials have more reliable quality against frost damages. However, capillarity in bricks remains a material property and needs to be considered. Here, a concept solution of brick wall with ventilation gap and vacuum insulated panel is presented. The refurbishment method requires proper consideration of building physics and careful assembly of undamaged moisture barrier. The care of water and humidity issues is essential. An air gap is a safety factor. In the case of ventilated walls, when the insulation layer is connected to the wall behind the ventilation layer (to the inner side of the air gap), the wall keeps generally dry.

Application The suitable areas of application are as follows: -

BUILDING TYPES – Multi rise buildings and single family dwellings CURRENT STRUCTURE OF EXTERNAL WALL – Lime-sand brick wall CLIMATIC ZONES – Dfc—cold, without dry season and with cold summer (Jyväskylä, North European).

Market potential The renovation method in this concept is very heavy structurally, and can take place only in certain circumstances. In southern Finland there are lots of houses and schools which were constructed during 1950-1970 with this construction type. In most of the cases the facades can not be changed, so the only way to remove the contaminated insulation layer and improve the structure is to remove the outer brick layer. The use of a vacuum insulated material is also studied in this concept. At the moment the price of the material is too high for common use but it could be used in special cases where the insulation layer has to be thin. The gap behind exterior brick layer is suitable for ventilation only in cold and dry climate zone.

Reasoning Brick wall usually suffer from some level of water penetration therefore, depending on the type of insulation used between brick layers, it may have been exposed to water and therefore lost the majority of it’s thermal properties which effects the energy performance of the building. Existing wet insulation layer usually has mould growth and microbes that are brought to indoor air. The insulation performance of vacuum insulated panels is 5 to 8 times better than conventional insulation. Therefore a high level of energy efficiency can be achieved with minimal disruption to the size of the external wall.


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Known problems related to refurbishment method Increases the thickness of the exterior wall structure (if carried out with traditional insulation materials like mineral wool). Need to find a suitable thickness of outer brickwork that doesn’t allow water penetration Failure of vacuum panels is usually caused by careless handling and transportation. Without protection the envelope is highly sensitive to mechanical impact, especially to point loads.

Cross section figure of the existing external wall


Cross section figure of the refurbishment concept

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Summary of the materials and layers thickness Renovation material list and application techniques (applies to refurbishment concept cross section below) are as follows: 1. New brick work or sand-lime brick work – 125mm 2. Ventilation space – 40mm 3. Rigid mineral wool insulation board – 30mm 4. EPS insulation sheet – vacuum insulation panel – EPS insulation– 5+20+5mm 5. Old interior concrete or brick envelope -125 mm 6. Surface treatment of interior cladding according to the room description.

Description of working methods Expansion joints, ventilation spaces, reinforcement and masonry ties will be according to the construction plans. Ties are placed to the vertical seams of vacuum insulation panels. Ventilation space, mortar fins must be removed from ventilation space. Rigid mineral wool insulation board covered with wind barrier coating, taping of seams according to the instructions of wind barrier insulation board supplier. This is required as vacuum insulation panel alone doesn’t work as a wind barrier in the structure. The rigid board also acts as a fire barrier for the ventilated space and the vacuum panel. EPS insulation sheet on both sides of vacuum insulation panel, fastening is made from adhesive mortar throughout to the base Old interior concrete or brick envelope, penetrations and interfaces are air sealed. The external surface should be smoothed so there are no sharp surfaces which could effect the installation of the vacuum panels.

Sealing of window and door frames Guidelines for sealing are given in the following: External sealant First, apply an external polyurethane foam outer sealant strip to the frame gap. eg. Illbruck Compriband (Tremco). This is permanently tight against driving rain but still ‘open’ to allow for water vapour to escape to the external atmosphere. Intermediate sealant The gap around the frame is sealed with elastic polyurethane foam eg. Illbruck Elastic Foam (Tremco) or similar product. Sealing should be homogenous and air-tight. Sealing is done from inside, before exterior and interior architraves are installed. If necessary, foam is added later on. as a retrofit action. The foam should fill the gap 2/3 of the depth of the gap measured from the interior surface. Internal sealant After the foam has dried, the interior seam between the frame and wall is sealed using an internal foam sealant strip and then elastic sealant e.g. Tremseal LM25 (Tremco) or similar product with M1 classification. Before installing the sealant strip, make sure the polyurethane foam layer is thick enough and then set the strip on fresh foam after the foam has stopped swelling. The sealant strip should be as deep as the gap is wide. The elastic sealant is then applied to close the gap, flush to the internal wall surface.


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Architraves are installed after sealing. The edges of architraves should be pressed tightly to the window/door frame and wall. Small gaps can be sealed with an acrylic sealant. In cases where intermediate sealants already exist, they should be examined to determine their suitability. Then they can either remain or be replaced, depending on their condition. External and Internal sealants can then be applied where necessary. The same procedure applies for all window and door jambs.

Ventilation upgrades required Fresh air inlets are needed because of improved air tightness of the exterior walls. Inlets can be integrated in the windows or installed to holes drilled through the walls. Exhaust ventilation should be considered.

Information about the performance values needed in the assessment Material

Thickness, mm

Properties Bulk density

Porosity

µdry

[-]

Specific Heat. Capacity [J/kgK]

[W/mk]

[-]

3

[Kg/m ]

dry

Brick

125

60

0,95

850

0,6

1,3

Mineral wool

30/100

1900

0,24

850

0,04

10

Vacuum insulation panel

0,02-0,03

0,008

Durability (with reference to required service life) and hygrothermal behaviour (in applied climate zone) Under normal weather conditions and with correct maintenance, bricks can last for a century or more. However, they are vulnerable to moisture, especially when exposed to freezing/thawing cycles. B1 - Jyväskylä weather data Criteria

Description

Values

Unit

Thermal performance

Transmission coefficient

Orig: 0,32; ref: 0,19; 0,21; 0,24

W/(m2K)

Thermal bridge effect

-

-

Conclusion

Good performance


-

kg/m2/year

Risk for frost damage

Results are not reliable

h/year

Results are not reliable

h/year

Moisture performance

T95% Risk for mould, corrosion T>0 C, RH>80%


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Risk for condensation, algae, decay Results are not reliable T>0 C, RH>95%

h/year

Conclusion Indoor climate

Overall conclusion


18,01-18,66

C

Conclusion

Very good performance

A significant amount of water passes through a brick work wall, and therefore part of the absorbed water of the exterior surface penetrates to the interior structures, in this case to the insulation and interior brick work layer. To improve the function of the original wall structure, the ventilation and drainage gap was added to the wall structure and the old mineral wool insulation was changed to a more energy efficient insulation (vacuum insulation panel). A ventilation gap enables the outer bricks to dry after rain and decreases the possibility of moisture damage. Because a vacuum insulation panel works as a vapour barrier in the refurbished structure, moisture and heat flow cannot move through the structure. Dehydration of interior brick work occurs only inwards and external structure dries only outwards. In External walls, one of the main moisture sources is driving rain. A high building, windy and open areas, and small eaves increase the stress of driving rain. Considering the Finnish climate conditions, wall structures are usually exposed to driving rain. In order that the structure can dry, there must be a ventilation gap between the outer brick work and wind barrier. In addition, when dehydration occurs the risk of mould growth is less in a ventilated wall structure. Simulation results show that changing the old mineral wool to new more energy efficient insulation, heat flow through the structure decreases. In addition, when the thickness of new insulation is increased the energy efficiency of the wall structure improves. However, the improvement is not prominent when the thickness of vacuum insulation panel is increased. The results of TOW calculation indicate that when repairing the original wall the possibility of frost formation increases on the outer brick work surface. The results of ventilated structures calculations are not reliable, because the actual air movement in the ventilation gap can not be taken into account in the calculations. The simulations of refurbished structures correspond to the structure without a ventilation gap. In the case of ventilated walls, the insulation layer, which comes after the ventilation layer, is generally dry.

Actions

The possibility of condensation is very high on the vacuum insulation panel outer surface. Thus, the risk of biological growth on the exterior surface of vacuum insulation panel must be kept in mind when an external wall is repaired. Because the aluminum foil of vacuum insulation panel surfaces is tight enough, air from the structure can not move to the indoor air. Thus, the risk of bad indoor air is very low (vacuum insulation panel must not be broken). When the outer layer of external wall is removed during the repair work, it is very important that the interior layer of the external wall is covered with a weatherproof shelter to avoid significant damp. Shelter can be removed until the outer brick work has been done. If the interior brick work gets wet the structure can be damaged and therefore indoor air quality can be got worse. In Finland the ventilation gap in this kind of wall structure is required.

Impact on energy demand for heating Will reduce energy demand compared to original.

Impact on energy demand for cooling No impact


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Impact on renewable energy use potential (using solar panels etc.) No impact

Impact on daylight No impact





Environmental impact of manufacture Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years, Refurbishment concept considers all refurbishment materials used: new external façade with sand lime brick, 30 mm rigid mineral wool and 20 mm vacuum insulation covered on both sides with EPS insulation (2 x 5 mm). No LCA result was found for vacuum insulation, in this calculation it is assumed that all 30 mm insulation is EPS. When LCA information for vacuum insulation will be available then a new calculation should be prepared. For existing wall, no construction materials are considered, only the impact from heating is calculated. U-value for existing wall is 0.32 W/m2 K, U-value for the concept is 0.24 W/m2 K. For heat flux and energy calculations heating degree days, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These are presented in the table below.

Cities Helsinki

HDD, +18oC

Heating energy type

4712

District heat

kg CO2 equ./kWh

Fossil energy consumption, MJ/kWh

Non-renewable rawmaterial consumption, kg/kWh

0.210

3.1

0.103


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180

Carbon footprint, kg CO2 eq/wall-m2/20 year

160 140 120 100 CF heating, Helsinki

80

CF, material

60 40 20 0 Existing, Helsinki

Ren. New sand lime facade +30 mm board+EPS, Helsinki

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating use. Heating type for Helsinki was district heating.

2 500

Fossil energy, MJ/wall-m2/20 year

2 000 1 500 from heating 1 000

from material

500 0 Existing, Helsinki


Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for Helsinki was district heating.


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Non renewable raw material kg/wallm2/20 year

350 300 250 200 from heating

150

from material

100 50 0 Existing, Helsinki


Figure. Non renewable raw-material consumption for existing- and refurbished walls. Heating type for Helsinki was district heating.

Environmental impact of manufacture The assessed environmental impact from manufacture is 38 kg CO2-eq from materials in one m2 of wall and 114 kg CO2 eq from 20 year heating.

Indoor air quality and acoustics Indoor air quality will be improved when possibly contaminated old insulation layer will be removed. Sealing will improve air-tightness.

Structural stability Stability is improved because the damaged brickwork is replaced with new. Requires careful demolition work.

Fire safety According to local regulations. Usually the ventilation gap should be closed or at least restricted between floors. There are also local demands on the outer surface of the wind barrier.

Aesthetic quality A wide variety of brick types are available so the quality of brick can be chosen based on budget and location constraints. In some cases recycled bricks can be used.

Effect on cultural heritage Original brickwork can be replaced with same type and colour to preserve the existing look of the façade if required. In some cases recycled bricks can be used.


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Life cycle costs Name: B1

Helsinki

Concept: Brick wall with ventilation gap and vacuum insulated panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Basic Heating energy (kWh/m2/a)

Refurbished 50

40

€/m2

€/m2

Basic renovation cost

95

95

Extra renovation cost

0

20

70

55

165

170

ECONOMICAL EFFECTS

Heating cost/20 y Life Cycle Cost

Need for care and maintenance The following measures are needed: -

Mortar - Mortar should be repointed every around every 25 years, depending on exact geographical location.

-

Efflorescence – A white, salty deposit on the brick surface is a sign of water penetration. This can be cleaned with a stiff brush. If hard deposits have formed, a chemical cleaner is needed.

Disturbance to the tenants and to the site Interior skin of external wall remains, so there should be no physical disturbance to tenants, only noise pollution.

Buildability Brick wall construction is an elementary building technique for many construction workers throughout Europe and is therefore a refurbishment technique which requires minimal further education, generally. Only basic building tools are required.


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Concept number 2 by VAHANEN – C1 Re-SOLAR

This concept is highly innovative. It presents a solution which offers external wall structure offering more than shelter; the structure is made active in generation and conservation of energy. Renewable energy can be utilised. The structural solutions collect solar energy and both retain it for the heating and protect the building from overheating. This allows more constant indoor temperature and saves energy costs by utilising solar energy. Currently the solution is beneficial in southern climates but it can be developed to energy saving item in more northern areas by enhancing the energy collection and retaining capacity by adding phase transformation material to the external surface of the insulation material (i.e. to the mineral wool). The materials utilized in the concept are fairly familiar and have been experienced to be durable in structural solutions – the main innovation is in the structural solution.

Application The suitable areas of application are as follows: BUILDING TYPES – Multi rise buildings RRENT STRUCTURE OF EXTERNAL WALL – Sandwich element panels CLIMATIC ZONES Dfc - cold, without dry season and with cold summer. (Jyväskylä, North European) Csa - temperate with dry, hot summer (Madrid, Spain)

Market potential As a product perhaps this concept would not produced on a large scale, but it could be used in southern climate zones in individual cases, where there is need to improve ventilation and indoor climate. It also provides a possibility to renew the exterior architecture of a building. Installation is quick with prefabricated elements.

Reasoning There is a need to research and push the boundaries of what is possible with current technology with regards to energy efficient refurbishment of buildings. This is an innovative refurbishment concept which is intelligent and can recognise when the indoor air requires additional heating or cooling. In the long term this would hopefully reduce the energy usage of the building. It also takes advantage of natural renewable heating resources (sunlight) to pre heat the outdoor air supply, which is used to heat the building. Since new cladding creates waterproof envelope and cover structures behind existing windows can remain which partially reduces costs and material consumption compared to basic façade renovation with window replacing.


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Summary of the materials and layers thickness Renovation material list and application techniques is as follows (applies to refurbishment concept cross section below): 1. South facing glazing 2. Ventilation space with venetian blinds – ~100 mm (50 mm air space behind blinds, minimum 20 mm air space in front of blinds to allow for glazing defection) 3. Phase changing material - ~15-25mm 4. New thermal insulation –100mm 5. Existing wall structure 6. Existing surface treatment 7. Fresh air intake 8. Heat exchange system


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9. Warm air circulated into internal spaces.

Description of working methods South facing glazing. The glazing is supported by a metal frame (steel or aluminium) which is fixed to the bearing structure of the existing building. Venetian blinds are installed in the air gap between the glazing and the new insulation layers. There is a removable panel located in the glazing which is used to access the blinds for maintenance. Exact fixing details of phase changing material boards varies depending on manufacturer and complexity of existing building external surface. Phase Changing Material is installed directly behind the blinds and it’s purpose is to store the excess heat which will be created when sunlight penetrates the external glazing and then release this heat to the structure when the external temperature falls. This should help to reduce temperature peaks in the structure. Make sure that insulation slabs are laid to bond with each other, and in particular at the corner of the building, window corners and door heads. Windows, corners and doors must be insulated using a whole slab to prevent possible cracks and cuts in the corner. Insulation is fixed to the external surface of the existing building with polyethylene plugs 3-4 pcs / m² Existing wall structure will be prepared so it is in good condition to receive the new layer of thermal insulation Existing surface treatment New supply air units will be installed according to manufacturer’s instructions.


3D cross section figure of the refurbishment concept

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Exploded 3D view of the refurbishment concept

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Structural fixing 3D view of the refurbishment concept

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Supply air units in a block of flats

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Supply air unit details

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Ventilation upgrades required See the previous diagrams

Information about the performance values needed in the assessment U-value - 0,25 W/m2K. Preliminary value based on the concept’s bare raw materials. There will be a difference when the constant air flow in the façade is taken into consideration in the calculation. Density values – Not yet calculated

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Although the concept is experimental, the basic material components have a proven history of durability (glass, steel, aluminium). The new glazed surface protects the old structure. Cross flow heat exchanger life expectancy is more than 10 years. The wall structure of C1 concept has been simulated with Comsol simulation software. It has been discovered that the use of C1 concept would not be profitable in Finland. This kind of wall is more suitable to countries with warmer climates e.g. South European countries. Because the simulations are not sufficient, the wall structure of C1 concept will be investigated further in the laboratory within the WP4. However, the simulation results shows that in Northern European countries phase transformation material should be added to the mineral wool external surface. On the contrary in South European countries (e.g. Spain), the phase transformation material may not be necessary.

Impact on energy demand for heating Reduces the building’s energy demand by using solar energy. Using Phase changing materials in the structure helps to introduce active temperature management to the building.

Impact on energy demand for cooling Concept can be used for cooling as well by installing reflective blinds. Using Phase changing materials in the structure helps to introduce active temperature management to the building.

Impact on renewable energy use potential (using solar panels etc.) Solar energy is used to heat the incoming air.

Impact on daylight Less direct daylight comes into the apartments. Provides possibilities for shading using blinds.

Environmental impact of manufacture Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which were considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years,


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Refurbishment concept considers materials used: glazing, venetian blind (expected to be aluminium), phase change material (expected to be gypsum) additional insulation (100 mm PUR). Concept contains also an air supply unit, heat exchanger and ducts, which are not taken into account. For existing wall no construction materials are considered, only the impact from heating is calculated. U-value for the existing wall is 0.44 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.25 W/m2 K. This is calculated according to the wall structure. When evaluating energy demand for heating, then it is also necessary to consider the utilization of natural heating resources (sunlight) to pre heat the outdoor air supply, and estimate accordingly. It is assumed that by lowering the U-value in energy calculations so that in Finland the U-value for concept structure is 0.21 W/m2 K and for Barcelona it is 0.15 W/m2 K (this reduces annual energy demand by 4 kWh/m2). This estimation gives just an idea about the potential benefits, but the real benefit of pre heated air was not known, this needs to be calculated in a real case. For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These are presented in the table below.

HDD, +18oC

Cities

Heating energy type

kg CO2 equ./kWh



Barcelona

1419

Gas

0.271

3.98

0.088

Helsinki

4712

District heat

0.210

3.1

0.103

30

Energy savings, kWh/wall-m2/a

25

Ren1 solar+phase change mat. + PUR

20 15


10 5 0 Barcelona

Helsinki

Figure. Energy savings compared to the existing wall. Ren1 is only preliminary value based on the concept’s raw materials. Ren2 is also only preliminary value which tries to guess the effect of pre heated air flow.


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80

Carbon footprint savings, kg/m2/20 year

70


60 50 40 30


20 10 0 Barcelona

-10

Helsinki

Figure. Carbon footprint savings compared to the existing wall. 1 400

Fossil energy savings, kg/wall-m2/20 year

1 200


1 000 800 600


400 200 0 -200

Barcelona

Helsinki

-400

Figure. Fossil energy savings compared to the existing wall.


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0

Non renewable raw-material savings, kg/wall-m2/20 year

-5

Barcelona

Helsinki

-10 -15


-20 -25 -30 -35


-40 -45 -50

Figure. Non-renewable raw-material savings compared to the existing wall.

CF heating

250

Carbon footprint, kg/wall-m2/20 year

CF, material 200 150 100 50 0 Existing Ren1 Ren2 Barcelona Barcelona Barcelona

Existing Helsinki

Ren1 Helsinki

Ren2 Helsinki

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating use. Heating type for Helsinki was district heating, and for Barcelona it was gas.


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4 500

from heating

4 000

from material


3 500 3 000 2 500 2 000 1 500 1 000 500 0 Existing Ren1 Ren2 Barcelona Barcelona Barcelona

Existing Helsinki

Ren1 Helsinki

Ren2 Helsinki

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for Helsinki was district heating and for Barcelona it was gas.

from heating Non renewable raw material, kg/wall-m2/20 year

120

from material

100 80 60 40 20 0 Existing Ren1 Ren2 Barcelona Barcelona Barcelona

Existing Helsinki

Ren1 Helsinki

Ren2 Helsinki

Figure. Non renewable raw-material consumption for existing- and refurbished walls. Heating type for Helsinki was district heating and for Barcelona it was gas.


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Indoor air quality and acoustics Improves indoor air quality, incoming air is filtered and warmed. The exterior structure reduces outdoor noise.

Structural stability Structural stability should be studied individually on a building by building basis. The new structure should be fixed to the bearing structure of the original building.

Fire safety The structure is closed between apartments so that fire can not spread horizontally or vertically.

Aesthetic quality Changes the appearance of the building façade dramatically. Skilful architectural work is needed.

Effect on cultural heritage Is not an ideal solution to use on buildings with historical value as it is unlikely that the dramatic alteration of the building façade will be acceptable. Life cycle costs Name: C1 Re-SOLAR Concept: ETICS applied to solid panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Helsinki

Basic 50

Ren1 34

Ren2 24

€/m2

€/m2

€/m2

75 0 63 138

90 25 43 158

95 15 30 140


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Name: C1 Re-SOLAR Concept: ETICS applied to solid panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Barcelona

Basic 16

Ren1 10

Ren2 6

€/m2

€/m2

€/m2

40 0 32 72

55 10 20 85

60 15 12 87

Need for care and maintenance This depends on the materials. Aluminium and glass need little maintenance. Glass needs to be cleaned from inside and outside from time to time. Apartment windows need to be cleaned (opening inside). Blinds need to be maintained. Ventilation filters must be replaced twice a year.

Disturbance to the tenants and to the site High level of disturbance to tenants. HVAC equipment has to be installed in the interior spaces. Fixing glazing to existing façade required large structural work. This will result in noise and air pollution.

Buildability Similar glass frame structures are currently being built in office buildings. Prefabricated elements, quick to install.


5

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Concept number 3 by VAHANEN – T1a. ETICS applied to sandwich element

This concept is of fairly familiar genre in most Northern countries; it is relatively simple and structurally safe, and fairly easy to construct with commonly available materials. The sandwich elements are abundant in the market areas of all Northern European countries, including the extensive export markets in Russia. In particular if the old outer surface of the external wall is in bad condition, this concept is favourable. The energy saving potential is highly dependent on the thickness of the additional insulation material, thus calculus for the decision making to meet the energy saving targets in the design phase is easy.

Application The concept is suitable for the following application areas: BUILDING TYPES – Multi rise buildings CURRENT STRUCTURE OF EXTERNAL WALL – Sandwich element panels CLIMATIC ZONES – Dfc—cold, without dry season and with cold summer (Jyväskylä, North European)

Market potential A three layer concrete wall structure is very common since 1960 in all European countries. The refurbishment method is well developed and the technology is widely spread. The thick and very thick mineral wool layers examined in this concept are relevant in Northern European countries. Mineral wool is commonly used in more Easterly European Countries and in Russia because of fire safety regulations. The refurbishment method can be used for solid concrete block walls and also for panel type walls.

Reasoning The largest proportion of heating energy – approx. 40-50% - is lost through the external walls. Reduces heating costs during winter, but keeps the outer shell of the building from heating up in the summer. Building gets new aesthetic façade design. Preserves net living space. Can lower the building’s energy consumption. Preserves building substructure by giving moisture protection and reduced temperature fluctuations. Widely used refurbishment technology in Finland, typically with mineral wool because of fire safety regulations that vary locally. Target is to study some problems related to this widely used method, study the hygrothermal behaviour with different parameters in exterior panel and develop the method further.

Known problems related to refurbishment method Algae growth on the surface of plaster Crack and holes can appear in plaster due to seasonal air temperature changes A safe level of insulation thickness needs to be determined Joints around windows and doors are prone to leaks.



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Summary of the materials and layers thickness Renovation material list and application techniques (applies to refurbishment concept cross section below): 1. Silicone based paint application. 2. Primer application and silicone resin finishing render – 1,5 mm 3. Smoothing reinforced layer applied to mineral wool. Comprised of reinforcing mesh layer inserted into a layer of adhesive – 10 mm 4. Mineral wool insulation – 100…300 mm 5. Insulation bonding adhesive should be applied to a smooth, uniform surface. 6. Existing sandwich element structure. Surface should be cleaned so all surface contaminants are removed. Structural stainless steel anchors are used to secure the outer shell to the inner bearing shell if necessary, to ensure stability. 4-5 steel anchors per panel. Extra care should be taken when sealing the indoor panel so that the seams are air-tight. This ensures that there no possible contaminants inside the existing wall are brought to the indoor air.

Description of working methods Finishing render must be set and dry for a minimum of 7 days before paint application. Use adhesive strips to create a boundary line between two shades of paint. Primer may be applied after the adhesive has dried out for at least 2 days. Primer must be thoroughly dried out (min. 24 hours) before render application. Application and exact thickness depends on the selected granulation and the grain of the façade. The thickness of the layer is usually equal to the average grain size of the mortar. The finishing layer should be floated while still wet. While drying out, the façade must be protected against strong sunlight, rain and wind. At low temperatures and high humidity, the mortar will take longer to dry. Before applying the first layer of adhesive, smooth and reinforce all corners of the building and the corners of the windows and doors using a corner batten reinforcing mesh already attached. To prevent cracks, stick the strips of reinforcing mesh of at least 300x200 mm above the corners of the windows and door heads and openings, at an angle of 45°. Then insert reinforced mesh into the freshly applied adhesive with min 100 mm overlap. When the adhesive with inserted mesh dries out, cut off the surplus mesh. Make sure that insulation slabs are laid to bond with each other, and in particular at the corner of the building, window corners and door heads. Windows, corners and doors must be insulated using a whole slab to prevent possible cracks and cuts in the corner. Insulation is fixed to the inner concrete panel with polyethylene plugs 3-4 pcs / m² no sooner than 24 hours after insulation is fixed to the wall. Adhesive is applied along the edge of the insulation slab and six dabs spread out over the slab. Apply with a trowel and ensure that enough adhesive so that it firmly adheres along all the edges of the slab. Possible surface irregularities and minimum deviations can be removed with rough sand paper attached to a float.


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Sealing of window and door frames Guidelines for sealing are given in the following: External sealantFirst, apply an external polyurethane foam outer sealant strip to the frame gap. eg. Illbruck Compriband (Tremco). This is permanently tight against driving rain but still ‘open’ to allow for water vapour to escape to the external atmosphere. Intermediate sealantThe gap around the frame is sealed with elastic polyurethane foam eg. Illbruck Elastic Foam (Tremco) or similar product. Sealing should be homogenous and air-tight. Sealing is done from inside, before exterior and interior architraves are installed. If necessary, foam is added later on. as a retrofit action. The foam should fill the gap 2/3 of the depth of the gap measured from the interior surface. Internal sealantAfter the foam has dried, the interior seam between the frame and wall is sealed using an internal foam sealant strip and then elastic sealant e.g. Tremseal LM25 (Tremco) or similar product with M1 classification. Before installing the sealant strip, make sure the polyurethane foam layer is thick enough and then set the strip on fresh foam after the foam has stopped swelling. The sealant strip should be as deep as the gap is wide. The elastic sealant is then applied to close the gap, flush to the internal wall surface. Architraves are installed after sealing. The edges of architraves should be pressed tightly to the window/door frame and wall. Small gaps can be sealed with an acrylic sealant. In cases where intermediate sealants already exist, they should be examined to determine their suitability. Then they can either remain or be replaced, depending on their condition. External and Internal sealants can then be applied where necessary. The same procedure applies for all window and door jambs.



Thickness, mm


Porosity [-]

[Kg/m3]


[W/mk]

[-]

dry

µdry

Lime cement plaster

2

1900

0,24

850

0,8

19

Mineral wool

80…300

60

0,95

850

0,04

1,3

Concrete

60…120

2300

0,18

850

1,6

180


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Manufacturer guarantees are offered for up to 30–40 years if the product is applied correctly, and maintained properly. Paint re application may be required earlier, depending on location, perhaps every 8-10 years. T1a - Jyväskylä weather data Criteria

Description

Values

Unit

Thermal performance


orig: 0,44; ref:0,17; 0,21; 0,28

W/(m2K)


-

-

Conclusion

Good performance



-

kg/m2/year

(review points:


Orig*1:4; ref*1: 1679-1722

h/year

1

* : outer surface of structure

T95%

2

* : insulation outer surface Risk for mould, corrosion (orig.)/ external insulation outer T>0 C, RH>80% surface (ref)

h/year Orig*2: 4777; 2 ref* : 3483-3668

Risk for condensation, algae, *3: insulation outer surface (orig.)/ external insulation outer decay surface (ref) T>0 C, RH>95%

Orig*3: 1223; ref*3: 2418-2533

Indoor climate

Overall conclusion

h/year

Conclusion

Values are significant high


17,31 to 19,1

Conclusion


C

For all facades one of the most critical sources of moisture is strong driving rain. The strain of driving rain on a facade and its harmful effects can be decreased with large overhanging eave structures. The thermal capacity of concrete sandwich walls is improved by adding a new insulation layer onto the old wall structure. As a result of adding a new insulation layer, the humidity technical function of the concrete sandwich wall changes slightly. Compared to the original wall, the simulation results show that adding the new mineral wool layer onto the old wall structure significantly reduces the heat flow through the structure. However, when the thickness of the new insulation layer is increased the energy efficiency of the wall structure does not increase significantly. According to the TOW calculations, the possibility of frost formation on the outer thermal insulation surface is significantly high in the case of repaired external walls. When the outer insulation layer is increased the possibility of frost formation increases also. In addition, the calculations show that there are great possibilities for mould growth in refurbished external walls. In the case of refurbished walls, the possibility of mould grow is smaller when the additional insulation layer is increased.


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Because of the high RH in the outer concrete layer (original external wall), there exists a significant possibility of corrosion growth in the reinforcement. Theoretically it could happen in conditions when RH>55% and the properties of the concrete become worse (carbonization of concrete booster causes corrosion of reinforcement). Actions

Mineral wool can survive the most negative factors for a long period of time, however plaster can be damaged easily, this is dependant on the quality of the compound and the quality of plaster producing (mixing). In order that mineral wool can survive from the damage, plaster and joints of external wall must not be damaged. If the protective plaster is damaged, then moisture can penetrate to the mineral wool which would result in a reduction of U-value. Before the repairing of the external wall, the condition of old exterior concrete cladding must be always checked (concrete and steel condition). The load bearing capacity of old concrete walls can be very bad. If only small damages have been found in the concrete cladding, then the repair can be executed. The risk of damage to the concrete cladding is reduced with a new insulation and plaster layer.





Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which were considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years, Refurbishment concept considers all materials used and three insulation levels 100 mm, 200 mm and 300 mm additional rockwool. For the façade render with float and set is used (25 mm). For existing wall no construction materials is considered only impact from heating is calculated. U-value for the existing wall is 0.44 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.21 W/m2 K U-value for 200 mm additional insulation is 0.14 W/m2 K. U-value for 300 mm additional insulation is 0.10 W/m2 K


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For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below.

Cities

HDD, +18oC

Heating energy type

Helsinki

4712

District heat

kg CO2 equ./kWh


0.210


3.1

0.103

45,00

Energy saving, kWh/wall-m2/a

40,00 35,00 30,00 25,00 Helsinki

20,00 15,00 10,00 5,00 0

50

100

150

200

250

300

350

Thickness of adittional insulation layer, mm

Figure. Energy savings compared to the existing wall.

Carbon footprint savings, kg/wall-m2/20 year

120 100 80 60 Helsinki

40 20 0 0

50

100

150

200

250

300


Figure. Carbon footprint savings compared to the existing wall.

350


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2 500

Fossil energy savings, MJ/wall-m2/20 year

2 000

1 500 Helsinki

1 000

500

0 0

50

100

150

200

250

300

350


Figure. Fossil energy savings compared to the existing wall. Non renewable raw material savings, kg/wall-m2/20 year

0 -1

0

50

100

150

200

250

300

350

-2 -3 -4

Helsinki

-5 -6 -7 -8




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250 200 150 CF heating, Helsinki

100

CF, material


Renovated (100 mm)

Renovated (200 mm)

Renovated (300 mm)

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating use. Heating type for Helsinki was district heating. 3 500


3 000 2 500 2 000 from heating

1 500

from material


Renovated (100 mm)

Renovated (200 mm)

Renovated (300 mm)



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Non renewable raw material, kg/wall-m2/20 year

120 100 80 60

from heating

40

from material


Renovated (100 mm)

Renovated (200 mm)

Renovated (300 mm)


Indoor air quality and acoustics Internal sealing stops the possible contaminants from the existing insulation go to the indoor air.

Structural stability Possible damaged fixing of exterior panel will be secured by new fixing.

Fire safety According to local regulations.

Aesthetic quality An almost infinite amount of colours are available for thermal plastering. Providing good quality workmanship is used to create the desired finish then the refurbishment method should enhance the external appearance of a building. The added thickness of the structure can cause problems with windows, doors, eaves, balconies etc.

Effect on cultural heritage If used to renovate an apartment building currently using a plaster finish then it is acceptable. If the plaster covers up some different existing material then it is necessary to consult local planning conditions.


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Life cycle costs Name: T1a

Helsinki

SusRef

Concept: ETICS applied to sandwich element Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool

Basic

100 mm

200 mm

300 mm

50

24

16

11

€/m2

€/m2

€/m2

€/m2


90

90

90

90


0

20

35

60

69

33

22

15

159

143

147

165

Heating energy (kWh/m2/a) ECONOMICAL EFFECTS


Need for care and maintenance Care should be taken during construction to ensure that there are no gaps in the finished surface as this will encourage water penetration. See durability assessment for more information.

Disturbance to the tenants and to the site Entire structure of external wall remains, so there should be no physical disturbance to tenants, only noise pollution. Sealing from inside will cause temporary relocation of fixed furniture and plinths along exterior wall.

Buildability Thermal plaster application is a common practice throughout Europe, and the technique doesn’t vary a lot from traditional plastering. Only basic building tools are required.


6

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Name of the concept – T1b. ETICS applied to sandwich element internal layer with smooth element surface

This concept is familiar in most Northern countries; it is relatively easy and structurally safe, and fairly easy to construct with commonly available materials. The sandwich elements are abundant in the market areas of all Northern European countries, including the extensive export markets in Russia. In particular if the old outer surface of the external wall is in bad condition, this concept is favourable. The energy saving potential is highly dependent on the thickness of the additional insulation material, thus calculus for the decision making in the design phase is easy: the first 10 cm of the additional thickness of extra insulation material linearly improve the energy saving capacity of the wall. The solutions can be applied with commonly available construction materials.

Application The suitable areas of application are as follows: BUILDING TYPES – Multi rise buildings CURRENT STRUCTURE OF EXTERNAL WALL – Sandwich element panels CLIMATIC ZONES – Dfc—cold, without dry season and with cold summer (Jyväskylä, North European)

Market potential A three layer concrete wall structure is very common since 1960 in all European countries. This concept includes removing the exterior panel and replacing the insulation layer. This is usually done in Finland due to casting technology which leaves the inner concrete panel surface very rough and makes fixing insulation tightly difficult. A growing concern of indoor air quality regards the removal of existing insulation layers which usually have mould and microbes. The refurbishment method is well developed and the technology is widely spread. The thick and very thick mineral wool layers examined in this concept are relevant in Northern European countries. Mineral wool is commonly used in more Easterly European Countries and in Russia because of fire safety regulations. The refurbishment method can also be used for solid concrete block walls, but is not suitable for panel type walls which dominate in Russia, Baltic countries and are common in Eastern Europe.

Reasoning The largest proportion of heating energy – approx. 40-50% - is lost through the external walls. Reduces heating costs during winter, but keeps the outer shell of the building from heating up in the summer. Building gets new aesthetic façade design and preserved net living space. Can lower the building’s energy consumption. Preserves building substructure by giving moisture protection and reduced temperature fluctuations. The outer panel is removed if the reinforcing is badly corrugated and the concrete has weathered beyond repair. This is estimated by laboratory tests. Widely used refurbishment technology in Finland, typically with mineral wool because of fire safety regulations that vary locally.


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Target is to study some problems related to this widely used method, study the building physical behaviour with different parameters like insulation thickness and develop the method further.

Known problems related to refurbishment method Known problems related the methods are listed in the following: Algae growth on the surface of plaster Crack and holes can appear in plaster due to seasonal air temperature changes A safe level of insulation thickness needs to be determined Joints around windows and doors are prone to leaks



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Summary of the materials and layers thickness Renovation material list and application techniques (applies to refurbishment concept cross section below): 1. Silicone based paint application. 2. Primer application and silicone resin finishing render – 1,5mm 3. Smoothing reinforced layer applied to mineral wool. Comprised of reinforcing mesh layer inserted into a layer of adhesive – 10mm 4. Mineral wool insulation – 100…400 mm 5. Insulation bonding adhesive should be applied to a smooth, uniform surface. 6. Reinforced concrete (existing internal element of sandwich panel). Surface should be cleaned so all surface contaminants are removed. Outer layer of sandwich element and insulation is removed when it is in bad condition, only internal element remains. Seams will be sealed from outside.

Description of working methods Finishing render must be set and dry for a minimum of 7 days before paint application. Use adhesive strips to create a boundary line between two shades of paint. Primer may be applied after the adhesive has dried out for at least 2 days. Primer must be thoroughly dried out (min. 24 hours) before render application. Application and exact thickness depends on the selected granulation and the grain of the façade. The thickness of the layer is usually equal to the average grain size of the mortar. The finishing layer should be floated while still wet. While drying out, the façade must be protected against strong sunlight, rain and wind. At low temperatures and high humidity, the mortar will take longer to dry. Before applying the first layer of adhesive, smooth and reinforce all corners of the building and the corners of the windows and doors using a corner batten reinforcing mesh already attached. To prevent cracks, stick the strips of reinforcing mesh of at least 300 x 200 mm above the corners of the windows and door heads and openings, at an angle of 45 °. Then insert reinforced mesh into the freshly applied adhesive with min 100 mm overlap. When the adhesive with inserted mesh dries out, cut off the surplus mesh. Make sure that insulation slabs are laid to bond with each other, and in particular at the corner of the building, window corners and door heads. Windows, corners and doors must be insulated using a whole slab to prevent possible cracks and cuts in the corner. Insulation is fixed to the inner concrete panel with polyethylene plugs 3-4 pcs/m² no sooner than 24 hours after insulation is fixed to the wall. Adhesive is applied along the edge of the insulation slab and six dabs spread out over the slab. Apply with a trowel and ensure that enough adhesive so that it firmly adheres along all the edges of the slab. Remove any surplus adhesive that may emerge from the previously attached insulation. Possible surface irregularities and minimum deviations can be removed with rough sand paper attached to a float.


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Sealing of window and door frames Guidelines for sealing are given in the following: External sealantFirst, apply an external polyurethane foam outer sealant strip to the frame gap. eg. Illbruck Compriband (Tremco). This is permanently tight against driving rain but still ‘open’ to allow for water vapour to escape to the external atmosphere. Intermediate sealantThe gap around the frame is sealed with elastic polyurethane foam eg. Illbruck Elastic Foam (Tremco) or similar product. Sealing should be homogenous and air-tight. Sealing is done from inside, before exterior and interior architraves are installed. If necessary, foam is added later on. as a retrofit action. The foam should fill the gap 2/3 of the depth of the gap measured from the interior surface. Internal sealantAfter the foam has dried, the interior seam between the frame and wall is sealed using an internal foam sealant strip and then elastic sealant e.g. Tremseal LM25 (Tremco) or similar product with M1 classification. Before installing the sealant strip, make sure the polyurethane foam layer is thick enough and then set the strip on fresh foam after the foam has stopped swelling. The sealant strip should be as deep as the gap is wide. The elastic sealant is then applied to close the gap, flush to the internal wall surface. Architraves are installed after sealing. The edges of architraves should be pressed tightly to the window/door frame and wall. Small gaps can be sealed with an acrylic sealant. In cases where intermediate sealants already exist, they should be examined to determine their suitability. Then they can either remain or be replaced, depending on their condition. External and Internal sealants can then be applied where necessary. The same procedure applies for all window and door jambs.



Thickness, mm


Porosity [-]


[W/mk]

[-]

3

[Kg/m ]

dry

µdry

cement plaster

10

2000

0,3

850

1,2

25

Mineral wool

100-400

60

0,95

850

0,04

1,3

Concrete

120

2300

0,18

850

1,6

180


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Manufacturer guarantees are offered for up to 30 – 40 years if the product is applied correctly, and maintained properly. Paint re application may be required earlier, depending on location. Perhaps every 8-10 years. T1c - Jyväskylä weather data Criteria

Description

Values

Unit

Thermal performance


orig: 0,44; ref:0,17; 0,21; 0,28

W/(m2K)


-

-

Conclusion

Good performance



-

(review points:


*1: outer surface of structure

T95%

h/year Orig*1: 1679; 1 ref* : 2243-2513

2

* : insulation layer (orig./ref.)

Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95%

Indoor climate

Overall conclusion

Actions

kg/m2/year

h/year Orig*2: 4777; 2 ref* : 3328-3433 Orig*2: 1223; ref*2: 1744-1820

h/year

Conclusion

Values are significant high


-

Conclusion


C

For all facades one of the most critical sources of moisture is strong driving rain. The strain of driving rain on a facade and its harmful effects can be decreased with large overhanging eave structures. The thermal capacity of concrete sandwich walls is improved by changing the old concrete and insulation layer to a new insulation and plaster layer. The result shows that changing old layers to new, the humidity technical function of the new external wall changes slightly. The simulation results show that by changing the old concrete and insulation layer to a new mineral wool layer with plaster surface, the heat flow through the structure decreases significantly. In addition, the repair method increases the energy efficiency of wall structure. However, when the thickness of new insulation layer is increased the energy efficiency of the wall structure does not increase significantly. According to the TOW calculations, the possibility of frost formation on the outer thermal insulation surface is higher in repaired walls than in the original wall structure. In addition, the risk of condensation is higher in repaired walls insulation layer. The calculations show that mould growth is lower in repaired structures than in the original wall. Mineral wool can survive the most negative factors for a long period of time, however plaster can be damaged easily, this is dependant on the quality of the compound and the quality of plaster producing (mixing). In order that mineral wool can survive from the damage, plaster and joints of external wall must not


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be damaged. If the protective plaster is damaged, then moisture can penetrate to the mineral wool which would result in a reduction of U-value. When the repair of the external wall is done, it is very important that the interior layer of the external wall is covered with a weatherproof shelter to avoid significant damp. If the interior concrete cladding gets wet the structure can be damaged and therefore indoor air quality can be get worse.





Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which were considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years, Refurbishment concept considers all materials used and four insulation levels 100 mm, 200 mm, 300 mm and 400 mm rockwool. For the façade render with float and set is used (25 mm). Calculation takes also into account the removal of the concrete element outer layer. For existing wall no construction materials is considered only impact from heating is calculated. U-value for the existing wall is 0.44 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.36 W/m2 K U-value for 200 mm additional insulation is 0.19 W/m2 K. U-value for 300 mm additional insulation is 0.13 W/m2 K U-value for 400 mm additional insulation is 0.10 W/m2 K For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below.


Cities

HDD, +18oC

Heating energy type

Helsinki

4712

District heat

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kg CO2 equ./kWh


0.210


3.1

0.103

45,00


40,00 35,00 30,00 25,00 Helsinki

20,00 15,00 10,00 5,00 0

100

200

300

400

500


Figure. Energy savings compared to the existing wall. 120


100 80 60 Helsinki

40 20 0 0 -20

100

200

300

400

500




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2 000 1 800


1 600 1 400 1 200 1 000

Helsinki

800 600 400 200 0 0

100

200

300

400

500



Non renewable raw-material savings, kg/wall-m2/20 year

0 -5

0

100

200

300

400

500

-10 -15 -20 Helsinki

-25 -30 -35 -40 -45




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250


CF heating, Helsinki 200

CF, material


Renovated (100 mm)

Renovated (200 mm)

Renovated (300 mm)

Renovated (400 mm)


3 500


3 000 2 500 2 000

from heating, Helsinki

1 500

from material


Renovated (100 mm)

Renovated (200 mm)

Renovated (400 mm)



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from heating, Helsinki

Non renewable raw-material, kg/wall-m2/20 year

160 140

from material

120 100 80 60 40 20 0 Existing, Helsinki

Renovated (100 mm)

Renovated (200 mm)

Renovated (300 mm)

Renovated (400 mm)


Indoor air quality and acoustics Indoor air quality will be improved when possibly contaminated old insulation layer will be removed. Sealing will improve air-tightness. Removing the exterior panel may weaken the acoustics, this should be checked with calculations individually.

Structural stability Improved. Exterior panel with possible damaged fixings is removed. The structure of the exterior wall is thoroughly checked.

Fire safety According to local regulations.

Aesthetic quality Changes the appearance of e.g. sandwich panel wall, the seams disappear if they are not faked on the surface. An almost infinite amount of colours are available for thermal plastering. Providing good quality workmanship is used to create the desired finish then the refurbishment method should enhance the external appearance of a building. The added thickness of the structure can cause problems with windows, doors, eaves, balconies etc. Thickness in this type can be adjusted. Different insulation thicknesses can be used to compensate the Uvalue in various parts of the building.



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Life cycle costs

Name: T1b Concept: ETICS applied to sandwich element Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Difference in heating cost/20 y Life Cycle Cost

Helsinki

SusRef

Basic 50

100 mm 41

200 mm 30

300 mm 15

400 mm 11

€/m2

€/m2

€/m2

€/m2

€/m2

90 0 69 159

90 20 56 166

90 35 41 166

90 60 21 171

90 90

15 195

Need for care and maintenance Care should be taken during construction to ensure that there are no gaps in the finished surface as this will encourage water penetration. See durability assessment for more information. Needs observing for cracks, re-painting is usually needed.

Disturbance to the tenants and to the site Entire structure of external wall remains, so there should be no physical disturbance to tenants, only noise and air pollution. Disturbance is greatest in the demolition phase. Noise and dust.

Buildability Similar techniques are being used in Finland and Europe. Thermal plaster application is a common practice throughout Europe, and the technique doesn’t vary a lot from traditional plastering. Only basic building tools are required.


7

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Name of the concept – T1c. ETICS applied to insulated panel RUS

This concept is familiar in most Northern countries; it is relatively easy and structurally safe, and fairly easy to construct with commonly available materials. The sandwich elements are abundant in the market areas of all Northern European countries, including the extensive export markets in Russia. In particular if the old outer surface of the external wall is in bad condition, this concept is favourable. The energy saving potential is highly dependent on the thickness of the additional insulation material, thus calculus for the decision making in the design phase is easy. Energy savings compared to the existing wall improves linearly along the additional thickness of extra insulation. The solutions can be applied with commonly available construction materials also in the export markets.

Application Suitable fields of application are as follows: -

BUILDING TYPES – Multi rise buildings CURRENT STRUCTURE OF EXTERNAL WALL – panels with mineral wool CLIMATIC ZONES – Dfc—cold, without dry season and with cold summer (Jyväskylä, North European) Russia, Ukraine, Belorussia and Baltic countries

Market potential Panel type concrete wall is very common since 1960 in Russia and previous Soviet countries. In many cases these houses have architecturally poor layouts and would need comprehensive refurbishment. The inhabitants are usually tenants and the owners are not very interested in refurbishment especially when energy is cheap. Financing for the refurbishment may be difficult to find. The refurbishment method is well developed and the technology is widely spread. Mineral wool is commonly used in more Easterly European Countries and in Russia because of fire safety regulations. The refurbishment method can also be used for solid concrete block walls.

Reasoning The largest proportion of heating energy – approx. 40-50% - is lost through the external walls. Reduces heating costs during winter, but keeps the outer shell of the building from heating up in the summer. Building gets new aesthetic façade design. Preserves net living space. Can lower the building’s energy consumption. Preserves building substructure by giving moisture protection and reduced temperature fluctuations. Solves problems of thermal bridges. Typical structure in Baltic Countries and Russia. Target is to study the building physical behaviour with different parameters like moisture in exterior panel and develop the method further so it is suitable for SPb markets.

Known problems related to refurbishment method Known problems related to the method are listed in the following:


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Algae growth on the surface of plaster Crack and holes can appear in plaster due to seasonal air temperature changes A safe level of insulation thickness needs to be determined Joints around windows and doors are prone to leaks Poor workmanship can also be a cause of surface damage problems It is difficult to study the condition of existing reinforcement in the panel




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Summary of the materials and layers thickness Structure of external panels is as follows: 1. Cement plaster – 10 mm 2. Mineral wool – 100…300 mm 3. Concrete external shell- 60 mm 4. Polystyrene, old- 110 mm 5. Concrete internal shell- 130 mm 6. Surface treatment as specified in the building specification

Description of working methods 1. The conditions of concrete and reinforcement within the structure should be checked 2. Panel surface is cleaned and all surface irregularities are removed from the wall 3. Mineral wool panels are stuck to the cleaned wall surface 4. After the glue is dried (after 24 hours) on the external mineral wool surface, the first layer of plaster is applied (approx. 4 mm), which is immediately reinforced with glass fibre mesh. 5. At the reinforcing mesh, plastic dowels are installed. The number of dowels depends on the height of the building (for buildings with a height less then 8 m use 6-8 dowels per m2, for multi storey buildings use 10-12 dowels per m2) 6. Top layer of plaster is applied (approx. 2 mm) 7. Primer application 8. Finishing application In the moment of placing and fixing heat insulated panels to the wall, should be avoided gaps between wall and thermal insulation. The distance between dowels in the horizontal direction should not be more than 70-80 mm and in the vertical direction, no more than 20-30 mm Anchoring length of dowels should be calculated In complex cases of facade thermal insulation renovation, all the building elements have to be considered, thermal insulation of roof structures, balconies, ventilation systems, installations etc. It’s recommended that the gluing mortar is applied without covering the whole wall surface but only applied in stripes or small dabs Extra care should be taken when sealing the indoor panel so that the seams are air-tight. This ensures that possible contaminants inside the existing wall are not brought to the indoor air. Sealing of window and door frames Guidelines for sealing are as follows: External sealantFirst, apply an external polyurethane foam outer sealant strip to the frame gap. eg. Illbruck Compriband (Tremco). This is permanently tight against driving rain but still ‘open’ to allow for water vapour to escape to the external atmosphere.


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Intermediate sealantThe gap around the frame is sealed with elastic polyurethane foam eg. Illbruck Elastic Foam (Tremco) or similar product. Sealing should be homogenous and air-tight. Sealing is done from inside, before exterior and interior architraves are installed. If necessary, foam is added later on. as a retrofit action. The foam should fill the gap 2/3 of the depth of the gap measured from the interior surface. Internal sealantAfter the foam has dried, the interior seam between the frame and wall is sealed using an internal foam sealant strip and then elastic sealant e.g. Tremseal LM25 (Tremco) or similar product with M1 classification. Before installing the sealant strip, make sure the polyurethane foam layer is thick enough and then set the strip on fresh foam after the foam has stopped swelling. The sealant strip should be as deep as the gap is wide. The elastic sealant is then applied to close the gap, flush to the internal wall surface. Architraves are installed after sealing. The edges of architraves should be pressed tightly to the window/door frame and wall. Small gaps can be sealed with an acrylic sealant. In cases where intermediate sealants already exist, they should be examined to determine their suitability. Then they can either remain or be replaced, depending on their condition. External and Internal sealants can then be applied where necessary. The same procedure applies for all window and door jambs.


Information about the performance values needed in the assessment U-value : U= 0,534 W/ m2k (basic structure) U= 0,228 W/m2k (with mineral wool thick 100 mm) U= 0,145 W/m2k (with mineral wool thick 200 mm) U= 0,107 W/m2k (with mineral wool thick 300 mm)


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Manufacturer guarantees are offered for up to 30 – 40 years if the product is applied correctly, and maintained properly. Paint re application may be required earlier, depending on location. Perhaps every 8-10 years. T1c – Russia weather data Criteria

Description

Values

Unit

Thermal performance


Orig: 0,53; ref:0,21; 0,15; 0,11

W/(m2K)


-

-

Conclusion

Good performance



-

kg/m2/year

(*in the worst point(s))


Orig*: 2276; ref*:1632-2358

h/year

Orig*: 6079; ref*:3431-3456

h/year

T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95%

Indoor climate

Overall conclusion

Orig*: 2399; ref*:1122 -1615

h/year

Conclusion

Values are high


-

Conclusion


C

External concrete wall with polystyrene insulation (basic structure). According to the simulation results of T1c original wall, by applying renovation techniques to concrete external shells in a very bad condition, the hydrothermal conditions inside the structure can be improved. Simulations were based on the following: structure orientation was not taken into account. In dependence on the measure place, the external shell exposed to frozen conditions for between 3 and 90 days during the year, external shell was in conditions where mould can appear from 110 to 240 days during the year, in conditions which have condensation and decay from 20 to 95 days during the year. The layer of polystyrene and internal layer of concrete wasn’t exposed. The most vulnerable place in the structure is the inner side of external shell (the place of conjunction between external shell and polystyrene), because most damages happen there and the RH in this part of wall is very high. Because of the high RH in the outer concrete layer, there exists a significant possibility of corrosion growth in the reinforcement. Theoretically it could happen in conditions when RH>55% and the properties of the concrete become worse (carbonization of concrete booster causes corrosion of reinforcement).


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External concrete wall with polystyrene insulation (renovated structure). Simulations were based on the following: structure orientation was not taken into account. In dependence on the measure place and the thickness of insulation, mineral wool is in frozen conditions from 10 to 90 days during the year, in conditions where mould or corrosion can appear from 120 to 130 days during the year, in conditions which have condensation and decay from 30 to 60 days during the year. In cases when the thickness of mineral wool is 100mm, the possibility of reinforcement corrosion isn’t big (approx. 20 days per year when RH>55%). In cases when the thickness of mineral wool is 200mm and 300mm, there is no possibility of reinforcement corrosion. After the application of the renovation method, the U-value of the structure is reduced. The condition of the concrete panel wall is improved, but it should be taken into account that, if the protective plaster is damaged, then moisture could penetrate to the mineral wool which would result in a reduction of U-value. The risk of damage to the concrete panels is reduced.

Actions

In the rehabilitated structure- the panel wall is no longer being exposed, and all negative anomalies happen in the layer of mineral wool insulation and in the plaster. Mineral wool can survive the most negative factors for a long period of time, however plaster can be damaged easily, this is dependant on the quality of the compound and the quality of plaster producing (mixing). In order that mineral wool can survive from the damage, plaster and joints of external wall must not be damaged.





Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which were considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years, Refurbishment concepts considers all materials used and three insulation levels 100 mm, 200 mm and 300 mm additional rockwool. For the façade render with float and set is used (25 mm).


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For existing wall no construction materials is considered only impact from heating is calculated. U-value for the existing wall is 0.53 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.21 W/m2 K U-value for 200 mm additional insulation is 0.15 W/m2 K. U-value for 300 mm additional insulation is 0.11 W/m2 K For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below. HDD,

kg CO2 eq/kWh



Cities

+18oC

Heating energy type

Moscow

4654

gas

0.271

3.98

0.088

Kiev

3809

gas

0.271

3.98

0.088

Minsk

4329

gas

0.271

3.98

0.088

Kaunas

4136

gas

0.271

3.98

0.088

Helsinki

4712

District heat

0.210

3.1

0.103

50,00


45,00 40,00 35,00 Moscow

30,00

Kiev

25,00

Minsk

20,00

Kaunas

15,00

Helsinki

10,00 5,00 0

50

100

150

200

250

300

350


Figure. Energy savings compared to the existing wall. . Heating type for Helsinki is district heating, for other locations, it is gas.


71 (232)

205 Carbon footprint savings, kg/wall-m2/20 year

185 165 145

Moscow

125

Kiev

105 85

Minsk

65

Kaunas

45

Helsinki

25 5 0

50

100

150

200

250

300

350




3 000 2 500

Moscow

2 000

Kiev

1 500

Minsk

1 000

Kaunas Helsinki

500 0 0

50

100

150

200

250

300



350

SUSREF

Non renewable raw material savings, kg/wall-m2/20 year

Sustainable Refurbishment of Building Facades and External Walls

72 (232)

10 5 0

Moscow 0

50

100

150

200

250

300

350

Kiev

-5

Minsk Kaunas

-10

Helsinki

-15 -20 Thickness of adittional insulation layer, mm

Figure. Non-renewable raw-material savings compared to the existing wall. 350

CF heating CF, material

200

Moscow

Kiev

Minsk

Kaunas

Helsinki

Exist. 100 mm 200 mm 300 mm

250



300

150 100 50




0



73 (232)

5 000

CF heating

4 500

CF, material


4 000 3 500

Moscow

3 000

Kiev

Minsk

Kaunas

Helsinki

2 500 2 000 1 500 1 000 500 0

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for Helsinki was district heating. 120

Moscow

Kiev

Minsk

Kaunas

Helsinki


100 80 60 40 20 0

CF heating

CF, material


Indoor air quality and acoustics Improves indoor air quality, if the ventilation is executed properly. The exterior structure reduces outdoor noise. Internal sealing stops the possible contaminants from the existing insulation go to the indoor air.

Structural stability High (own weight of facade structure isn’t big, should be calculated the length of anchoring). Stiffness of mineral wool should be taken into account and consider.


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Fire safety High (thermal insulation- mineral wool). According to local regulations.

Aesthetic quality An almost infinite amount of colours are available for thermal plastering. Providing good quality workmanship is used to create the desired finish then the refurbishment method should enhance the external appearance of a building. The added thickness of the structure can cause problems with windows, doors, eaves, balconies etc. Thickness in this type can be adjusted. Different insulation thicknesses can be used to compensate the Uvalue in various parts of the building.



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Life cycle costs Name: T1c Concept: ETICS applied to insulated panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Helsinki

SusRef

Basic 53

100 mm 21

200 mm 15

300 mm 11

€/m2

€/m 2

€/m2

€/m 2

90 0 73 163

90 20 29 139

90 35 21 146

90 80 15 185


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Name: T1c Concept: ETICS applied to insulated panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Moscow

SusRef

Basic 59

100 mm 23

200 mm 17

300 mm 12

€/m2

€/m2

€/m2

€/m2

65 0 74 139

65 15 29 109

65 25 21 111

65 55 15 135


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Kaunas

SusRef

Basic 53

100 mm 21

200 mm 15

300 mm 11

€/m2

€/m2

€/m2

€/m2

65 0 66 131

65 15 26 106

65 25 19 109

65 55 14 134


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Kiev

SusRef

Basic 48

100 mm 19

200 mm 14

300 mm 10

€/m2

€/m2

€/m2

€/m2

60 0 60 120

60 15 24 99

60 25 18 103

60 55 13 128


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Name: T1c Concept: ETICS applied to insulated panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a)

Minsk

SusRef

Basic 55

100 mm 22

200 mm 16

300 mm 11

€/m2

€/m2

€/m2

€/m2

ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

60 0 69 129

60 15 28 103

60 25 20 105

60 55 14 129

Need for care and maintenance Thermal insulation could be easily changed after determined period of time. Care should be taken during construction to ensure that there are no gaps in the finished surface as this will encourage water penetration. Cracks should be monitored, re-painting is usually needed. See durability assessment for more information.

Disturbance to the tenants and to the site Execution of works could be done without eviction. A high level of noise pollution disturbance to tenants.

Buildability Thermal plaster application is a common practice throughout Europe, and the technique doesn’t vary a lot from traditional plastering. Only basic building tools are required and special pump for spreading concrete on the thermal insulation surface.

SUSREF Sustainable Refurbishment of Building Facades and External Walls 8

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Name of the concept – T1d. ETICS applied to solid panel RUS

This concept is familiar in most Northern countries; it is relatively easy and structurally safe, and fairly easy to construct with commonly available materials. The sandwich elements are abundant in the market areas of all Northern European countries, including the extensive export markets in Russia. In particular if the old outer surface of the external wall is in bad condition, this concept is favourable. The energy saving potential is highly dependent on the thickness of the additional insulation material, but the life cycle costs are clearly dependant on the location (i.e. Moscow or Kiev). Energy savings compared to the existing wall improves linearly along the additional thickness of extra insulation. The solutions can be applied with commonly available construction materials, and there is a large building stock to which this is applicable in the post-Soviet states.

Application The suitable areas of application are as follows: BUILDING TYPES – Multi rise buildings CURRENT STRUCTURE OF EXTERNAL WALL – Prefabricated solid panels CLIMATIC ZONES – Dfc—cold, without dry season and with cold summer (Jyväskylä, North European) Russia, Ukraine, Belorussia and Baltic countries

Market potential The building type with a solid lightweight concrete wall was very commonly built during 1950-1960 in Russia and post Soviet states. The refurbishment method is well developed and the technology is widely spread. Mineral wool is commonly used in more Easterly European Countries and in Russia because of fire safety regulations.

Reasoning The largest proportion of heating energy – approx. 40-50% - is lost through the external walls. Reduces heating costs during winter, but keeps the outer shell of the building from heating up in the summer. Building gets new aesthetic facade design. Preserves net living space. Can lower the building’s energy consumption. Preserves building substructure by giving moisture protection and reduced temperature fluctuations. Solves the problems of thermal bridges. Typical structure in post USSR territories. Target is to study the building physical behaviour with different parameters like varying thickness of insulation layer and develop the method further so that it is suitable for SPb markets.

Known problems related to refurbishment method Algae growth on the surface of plaster Crack and holes can appear in plaster due to seasonal air temperature changes A safe level of insulation thickness needs to be determined

SUSREF Sustainable Refurbishment of Building Facades and External Walls Joints around windows and doors are prone to leaks Poor workmanship can also be a cause of surface damage problems


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Details of panels conjunction

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Summary of the materials and layers thickness Structure of external panels 1. Cement plaster- 10mm 2. Mineral wool- 100…300mm 3. Ceramic tiles – 8mm 4. Prefabricated solid lightweight concrete panels – 400 mm 5. Surface treatment as specified in the building specification

Description of working methods 1. The conditions of concrete and reinforcement within the structure should be checked 2. Existing surface is cleaned and all surface irregularities are removed from the wall 3. Mineral wool panels are fixed to the cleaned wall surface 4. The first layer of plaster is applied (approx. 6 mm) on the external mineral wool surface, which is immediately reinforced with glass fibre mesh. 5. At the reinforcing mesh, plastic dowels are installed. The number of dowels depends on the height of the building (for buildings with a height less then 8 m use 6-8 dowels per m2, for multi storey buildings use 10-12 dowels per m2) 6. Top layer of plaster is applied (approx. 4 mm) 7. Primer application 8. Finishing application During placing and fixing of heat insulated panels to the wall, try to avoid gaps between wall and thermal insulation. The distance between dowels in the horizontal direction should not be more than 70-80 mm and in the vertical direction, no more than 20-30 mm Anchoring length of dowels should be calculated In complex cases of facade thermal insulation, all the building elements have to be considered, thermal insulation of roof structures, balconies, ventilation systems, installations etc.

Description of plastering working methods Finishing render must be set and dry for a minimum of 7 days before paint application. Use adhesive strips to create a boundary line between two shades of paint. Primer may be applied after the adhesive has dried out for at least 2 days. Primer must be thoroughly dried out (min. 24 hours) before render application. Application and exact thickness depends on the selected granulation and the grain of the facade. The thickness of the layer is usually equal to the average grain size of the mortar. The finishing layer should be floated while still wet. While drying out, the facade must be protected against strong sunlight, rain and wind. At low temperatures and high humidity, the mortar will take longer to dry. Before applying the first layer of adhesive, smooth and reinforce all corners of the building and the corners of the windows and doors using a corner batten reinforcing mesh already attached.


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To prevent cracks, stick the strips of reinforcing mesh of at least 300x200 mm above the corners of the windows and door heads and openings, at an angle of 45°. Then insert reinforced mesh into the freshly applied adhesive with min 100 mm overlap. When the adhesive with inserted mesh dries out, cut off the surplus mesh. Make sure that insulation slabs are laid to bond with each other, and in particular at the corner of the building, window corners and door heads. Windows, corners and doors must be insulated using a whole slab to prevent possible cracks and cuts in the corner. Insulation is fixed to the inner concrete panel with polyethylene plugs 6-8 pcs / m² no sooner than 24 hours after insulation is fixed to the wall. Adhesive is applied along the edge of the insulation slab and six dabs spread out over the slab. Apply with a trowel and ensure that enough adhesive so that it firmly adheres along all the edges of the slab. Remove any surplus adhesive that may emerge from the previously attached insulation. Possible surface irregularities and minimum deviations can be removed with rough sand paper attached to a float.

Sealing of window and door frames Guidelines for sealing are given in the following: External sealant First, apply an external polyurethane foam outer sealant strip to the frame gap. e.g. Illbruck Compriband (Tremco). This is permanently tight against driving rain but still ‘open’ to allow for water vapour to escape to the external atmosphere. Intermediate sealant The gap around the frame is sealed with elastic polyurethane foam e.g. Illbruck Elastic Foam (Tremco) or similar product. Sealing should be homogenous and air-tight. Sealing is done from inside, before exterior and interior architraves are installed. If necessary, foam is added later on. as a retrofit action. The foam should fill the gap 2/3 of the depth of the gap measured from the interior surface. Internal sealant After the foam has dried, the interior seam between the frame and wall is sealed using an internal foam sealant strip and then elastic sealant e.g. Tremseal LM25 (Tremco) or similar product with M1 classification. Before installing the sealant strip, make sure the polyurethane foam layer is thick enough and then set the strip on fresh foam after the foam has stopped swelling. The sealant strip should be as deep as the gap is wide. The elastic sealant is then applied to close the gap, flush to the internal wall surface. Architraves are installed after sealing. The edges of architraves should be pressed tightly to the window/door frame and wall. Small gaps can be sealed with an acrylic sealant. In cases where intermediate sealants already exist, they should be examined to determine their suitability. Then they can either remain or be replaced, depending on their condition. External and Internal sealants can then be applied where necessary. The same procedure applies for all window and door jambs.



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Information about the performance values needed in the assessment U-value: U=0,862 W/m2k (Basic structure) U=0,275 W/m2k (with mineral wool thick 100mm) U=0,162 W/m2k (with mineral wool thick 200mm) U=0,115 W/m2k (with mineral wool thick 300mm)

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Manufacturer guarantees are offered for up to 30 – 40 years if the product is applied correctly, and maintained properly. Paint re application may be required earlier, depending on location. Perhaps every 8-10 years.

T1d – Russia weather data Criteria

Description

Values

Thermal performance


Orig: 0,86; ref: W/(m2K) 0,28; 0,16; 0,12


-

Conclusion

Good performance

Moisture performance (*in the Annual moisture accumulation worst point(s)) Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Conclusion

Unit

-

-

kg/m2/year

Orig*: 2381; ref*: 20-115

h/year

h/year Orig*: 8261; ref*: 2900-2911 Orig*: 5724; ref*: 638-800 Just sufficient

h/year

SUSREF Sustainable Refurbishment of Building Facades and External Walls Indoor climate

Overall conclusion

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-

C

Conclusion


External panel wall from light weight concrete (basic structure). According to the simulation results of T1d original wall, the external side of the concrete panel wall is presumed to be in a very bad condition and by applying renovation techniques the hydrothermal conditions inside the structure can be improved. Simulations were based on the following: structure orientation was not taken into account. In dependence on the measure place and the thickness of insulation, the external side of panel wall(approx. 150mm from outer surface) exposed to frozen condition from 56 to 93 days during the year, structure was in conditions where mould can appear almost the whole year, in conditions which have condensation and decay from 210 to 230 days during the year. The internal side of concrete panel wall wasn’t exposed. Because of the high RH in the outer concrete layer, there exists a significant possibility of corrosion growth in the reinforcement. Theoretically it could happen in conditions when RH>55% and the properties of the concrete become worse (carbonization of concrete booster causes corrosion of reinforcement). External panel wall from light weight concrete (renovated structure). The place of connection between mineral wool and plaster is in frozen conditions for 93 days during the year, in conditions where mould can appear for 123 days during the year, and in conditions which have condensation and decay for 34 days during the year. In cases when the thickness of mineral wool is 100mm, the possibility of reinforcement corrosion isn’t big (approx. 47 days per year when RH>55%). In cases when the thickness of mineral wool is 200mm and 300mm, there is no possibility of reinforcement corrosion.

Actions

After the application of the renovation method, the U-value of the structure is reduced. The condition of the concrete panel wall is improved, but it should be taken into account that, if the protective plaster is damaged, then moisture could penetrate to the mineral wool which would result in a reduction of U-value. The risk of damage to the concrete panels is reduced. In the rehabilitated structure- the panel wall is no longer being exposed, and all negative anomalies happen in the layer of mineral wool insulation and in the plaster. Mineral wool can survive the most negative factors for a long period of time, however plaster can be damaged easily, this is dependant on the quality of the compound and the quality of plaster producing (mixing). In order that mineral wool can survive from the damage, plaster and joints of external wall must not be damaged.




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Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which were considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the following assumptions: Life span is 20 years, Refurbishment concept considers all materials used and three insulation levels 100 mm, 200 mm and 300 mm additional rockwool. For the façade render with float and set is used (25 mm). For existing wall no construction materials is considered only impact from heating is calculated. U-value for the existing wall is 0.862 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.275 W/m2 K U-value for 200 mm additional insulation is 0.162 W/m2 K. U-value for 300 mm additional insulation is 0.115 W/m2 K For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below. HDD,

kg CO2 eq/kWh



Cities

+18oC

Heating energy type

Moscow

4654

gas

0.271

3.98

0.088

Kiev

3809

gas

0.271

3.98

0.088

Minsk

4329

gas

0.271

3.98

0.088

Kaunas

4136

gas

0.271

3.98

0.088


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95,00 85,00 75,00 65,00 55,00

Moscow

45,00

Kiev

35,00

Minsk

25,00

Kaunas

15,00 5,00 0

50

100

150

200

250

300

350


Figure. Energy savings compared to the existing wall. Heating type for all locations is gas. 450


400 350 300 250

Moscow

200

Kiev

150

Minsk

100

Kaunas

50 0 0

50

100

150

200

250



300

350


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7 000


6 000 5 000 4 000

Moscow

3 000

Kiev Minsk

2 000

Kaunas

1 000 0 0

50

100

150

200

250

300

350


Figure. Fossil energy savings compared to the existing wall. Non renewable raw-material savings, kg/wall-m2/20 year

70 60 50 40

Moscow

30

Kiev Minsk

20

Kaunas

10 0 0

50

100

150

200

250

300



350


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600

Moscow Carbon footprint, kg CO2 eq/wall-m2/20 year

500

Minsk

Kiev

Kaunas

400 300 200 100 0 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 mm mm mm mm mm mm mm mm mm mm mm mm CF heating

CF, material

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating use. Heating type for all locations is gas.

9 000 8 000

Moscow

Kiev

Minsk

Kaunas


7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 mm mm mm mm mm mm mm mm mm mm mm mm from heating

from material

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for all locations is gas.


180 160

Moscow

Kiev

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Minsk

Kaunas


140 120 100 80 60 40 20 0 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 Exist. 100 200 300 mm mm mm mm mm mm mm mm mm mm mm mm from heating

from material

Figure. Non renewable raw-material consumption for existing- and refurbished walls. Heating type for all locations is gas.

Indoor air quality and acoustics Improves indoor air quality, if the ventilation is executed properly. The exterior structure reduces outdoor noise.

Structural stability High (own weight of facade structure isn’t big, should be calculated the length of anchoring). Stiffness of mineral wool should be taken into account and consider.

Fire safety High (thermal insulation- mineral wool). According to local regulations.

Aesthetic quality An almost infinite amount of colours are available for thermal plastering. Providing good quality workmanship is used to create the desired finish then the refurbishment method should enhance the external appearance of a building. The added thickness of the structure can cause problems with windows, doors, eaves, balconies etc. Thickness in this type can be adjusted. Different insulation thicknesses can be used to compensate the Uvalue in various parts of the building.



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Life cycle costs Name: T1d

Moscow

SusRef

Concept: ETICS applied to solid panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool

100 mm

200 mm

300 mm

96

31

18

13

€/m2

€/m2

€/m2

€/m2


65

65

65

65


0

10

15

20

Heating cost/20 y

120

39

23

16

Life Cycle Cost

185

114

103

101


Basic


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Name: T1d

Kiev

SusRef


100 mm

200 mm

300 mm

79

25

35

31

€/m2

€/m2

€/m2

€/m2


60

60

60

60


0

10

15

20

99

31

44

39

159

101

119

119



Basic


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Name: T1d

Minsk

SusRef


Basic

100 mm

200 mm

300 mm

90

29

17

12

€/m2

€/m2

€/m2

€/m2


65

65

65

65


0

10

15

20

Heating cost/20 y

113

36

21

15

Life Cycle Cost

178

111

101

100


Need for care and maintenance Thermal insulation could be easily changed after determined period of time. Care should be taken during construction to ensure that there are no gaps in the finished surface as this will encourage water penetration. Cracks should be monitored, re-painting is usually needed. See durability assessment for more information.

Disturbance to the tenants and to the site Execution of works could be done without eviction. A high level of noise pollution disturbance to tenants.

Buildability Thermal plaster application is a common practice throughout Europe, and the technique doesn’t vary a lot from traditional plastering.


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Only basic building tools are required and special pump for spreading concrete on the thermal insulation surface.


9

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NAME OF THE CONCEPT – EKK1 - Filling brick wall cavities with carbamide resin foam.

This concept is valid for large amount of building stock with load bearing brick walls, frequently encountered in the Eastern Europe. The method reduces a building's energy consumption and increases the tightness of the structure. This refurbishment method is easy to adopt in particular throughout Eastern-Europe region, as the cost is not too high and workmanship can be mastered fairly easily. As the result of carbamide foam insulation both the LCA and LCC improve in the targeted market area.

Application BUILDING TYPES – Single- and multi-storey buildings CURRENT STRUCTURE OF EXTERNAL WALL –Brick walls with air cavity or decayed wool insulation (D3.1 Table 3, type 4A) CLIMATIC ZONES – Dfb – cold, without dry season and with warm summer. Zone 3 - North Europe (Based on D3.1 document), partially Zone 2 – Central (Eastern) Europe (Ukraine)

Market potential Below described refurbishment concept takes into account 430mm sand-lime brick wall with decayed and sunken old mineral wool or just cavities without insulation. This type of brick wall is most represented in the Baltic countries, partially in Russia and Ukraine. Refurbishment method applied to the climatic zone 3, North European and partially to the zone 2, Central (Eastern) European countries. This refurbishment concept is intended to load-bearing brick wall which has air cavities or decayed and sunken old mineral wool between the brick layers. Wall thickness may varied 380…560mm and old insulation or cavity thickness is 60…140mm. Outer layer can be sand-lime, clay or perforated clay brick. Method is also suitable for that kind of heritage buildings which have clay brick walls with air cavities (cavity thickness usually ~100mm).

Reasoning Soviet-era building quality was very irregular. Mineral wool is used in the construction of the wall has lost its structural stability over time, sometimes a half-empty or heat insulating gaps in the insulation is not used at all. Used mineral wool thermal resistance is about 40% worse than ordinary wool or foam insulation materials nowadays. Filling an existing air cavities decrease blowing through and heat losses as well. Operation can be done without the disassembly of the wall structure and possibility to work only outside or only inside. Not an expensive method and time cost is not big. Solution is suitable for those buildings where we cannot insulate outside or even inside (heritage buildings etc.). Building outside measures and room spaces are remains as before refurbishment.


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Known problems related to refurbishment method Disadvantage may be carrying out the method in closed wall structure: how to check the foam steady flow and expansion. Thermal conductivity difference between old and refurbished wall is quite small. The water absorption value of carbamide resin foam needs to be check out. Hydrothermal conditions of the wall have to be calculated considering the finishing layers.


Cross section figure of the existing external wall 1/2

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Cross section figure of the existing external wall 2/2

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CROSS SECTION FIGURE OF THE REFURBISHMENT CONCEPT 1/2


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CROSS SECTION FIGURE OF THE REFURBISHMENT CONCEPT 2/2


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Summary of the materials and layers thickness 1. Natural sand-lime brick – 120mm 2. Existing air gap or decayed and sunken wool insulation. Free air space filled with carbamide resin foam – 60mm ( =8-15 kg/m³, design=0.04 W/m•K, µ=2-4), water receptivity: 0.3% Vol. 3. Sand-lime load bearing brick – 250mm 4. Cement or cement-lime plaster – 15mm

Description of working methods 1. Determine the extent of voids inside the wall 2. Drill holes to the masonry joints considering the suitable diameter, depth and distance. 3. Fill wall through the holes with carbamide resin foam. 4. Remove excessive foam outside the holes and around the window or door frames in necessary. 5. Restore the finishing around the drilled holes.

Sealing of window and door frames Window and door frames remain as they were before refurbishment.

Ventilation upgrades required When the whole wall water vapour diffusion transmission is sufficient then ventilation upgrade is not relevant. Only method itself does not require ventilation upgrade.

Information about the performance values needed in the assessment U = 1.47 W/m2K, in case of air cavity – existing construction U = 1.15 W/m2K, in case of mineral wool – existing construction U = 1.11 W/m2K, insulated with carbamide resin foam (Harnstoff-Formaldehydharz (UF)-Ortschaum) 50% + existing mineral wool 50% U = 1.07 W/m2K, insulated totally with carbamide resin foam (Harnstoff-Formaldehydharz (UF)Ortschaum) Note: - thermal bridges 10% are taken into account in the insulation layer (60mm)


Material

Sand-lime brick Cement (-lime) plaster Mineral wool (old) Carbamide resin foam

Thickness, mm

Bulk density [kg/m3]

Porosity [-]

120 / 250

2000

0.23

15

1800

0.31

60

100

0.96

60 (varies)

12 (±20%)

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Properties Specific Heat. Capacity [J/kgK] 900

[W/mk]

µ [-]

1.1

7

1130

0.93

8

840

0.07

1.3

0.04

2…4

design

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) In Northern European weather conditions, this kind of brick wall (sand-lime brick) is quite durable itself, but the physical performance is not good. Brick wall with cavity only or decayed and sunken mineral wool (existing wall) This wall passes through a quite considerable amount of moisture especially because of driving rain. The inner surface of the wall is cold at the winter time and frequently moist at the autumn and early spring time – it is a good condition for mould progress. This wall has also blowing through and acoustic problems. Brick wall filling cavities with carbamide resin foam (refurbished wall) The easiest and cheapest way to improve the physical performance of the wall is filling the wall cavities with carbamide resin foam. The foam characteristics are quite suitable for that kind of wall – it has a good water vapour diffusion transmission but has small water receptivity (hydrophobia). Also acoustic barrier performance improved significantly. Only unfavourable thing is that we cannot practically decrease the impact of thermal bridges and therefore the overall U-value of the refurbished wall is big. Manufacturer guarantees for this carbamide resin foam 30 years. Approximate service life is 50 years.


Criteria Thermal performance


Indoor climate

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Description Values Transmission coefficient 0,554 Thermal bridge effect Conclusion Just sufficient Annual moisture accumulation -0,131

Unit W/(m2K) -

Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Conclusion Lowest indoor surface temperature Conclusion

h/year

23 167

kg/m2/year

h/year h/year

8 Just sufficient 17,8

C

Good performance

Impact on energy demand for heating Construction heat loss is 193,0 kWh/m2 – 120mm sand-lime brick; 60mm air-cavity; 250mm sand-lime brick; 15mm plaster) Construction heat loss is 151,6 kWh/m2 – (120mm sand-lime brick; 60mm mineral wool; 250mm sandlime brick; 15mm plaster) Construction heat loss is 146,3 kWh/m2 – (120mm sand-lime brick; 30mm carbamide resin foam 30mm mineral wool ; 250mm sand-lime brick; 15mm plaster) Construction heat loss is 141,3 kWh/m2 – (120mm sand-lime brick; 60mm carbamide resin foam; 250mm sand-lime brick; 15mm plaster) The heat loss values calculated based on Estonian normal-year average temperatures.

Impact on energy demand for cooling Method gives slight isolating effect.

Impact on renewable energy use potential (using solar panels etc.) No impact.

Impact on daylight No impact.

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating.


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Impact parameters considered are carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the next assumptions: Life span is 20 year, For existing and refurbished wall only impact from heating energy is considered. Concept uses thermo reflective heat insulation (TRI), which environmental impact was not known. U-values were used as shown above. For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below.

Climatic zones (Dfb) Cities

HDD, +18oC

Heating energy type

Carbon footprint, kg CO2 eq/kWh

Fossil energy consumption,

Russia

Moscow

4654

gas

0.271

3.98

0.088

Ukraine

Kiev

3809

gas

0.271

3.1

0.088

Nordic

Tallinn

4562

gas

0.271

3.1

0.088

MJ/kWh

50 45 40


35 30 25

Moscow

20

Kiev

15

Tallinn

10 5 0 Ren. with carbamide resin (60 mm cavity wall)

Ren. with carbamide resin (60 mm cavity with min. wool)


Non renewable raw-material consumption, kg/kWh


108 (232)


255 205 155 Moscow 105

Kiev Tallinn

55 5 Ren. carbamide resin (60 mm cavity wall)

Ren. carbamide resin (60 mm cavity with poor wool)



3 500 3 000 2 500 Moscow

2 000

Kiev

1 500

Tallinn

1 000 500 0 Ren. carbamide resin (60 mm cavity wall)




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Non-renewable raw material savings, kg/wall-m2/20 year

90 80 70 60 50

Moscow

40

Kiev

30

Tallinn

20 10 0 Ren. carbamide resin (60 mm cavity wall)



1000

Carbon footprint, kg Co2 eq /wall-m2/20 year

900 800

Existing wall, empty cavity

700 600

Renovated (60 mm cavity with carbamide resin)

500

Existing wall, cavity with wool

400 300

Renovated (60 mm cavity with wool and carbamide resin)

200 100 0 CF, material

CF heating, Moscow

CF heating, Kiev

CF heating, Tallinn

Figure. Carbon footprint for existing-and refurbished walls. Heating type for all locations is gas.


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14 000

Fossil energy, MJ/wall-m2/period

12 000 10 000


8 000 6 000

Ren. carbamide resin (60 mm cavity wall)

4 000

Existing wall, cavity with wool

2 000


0 Embodied fossil energy, material

Fossil Fossil energy, energy, heating, heating, Kiev Moscow

Fossil energy, heating, Tallinn

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for all location is gas.

1000 kg CO2 eq /m2/20 year

900 800 700

Existing brick wall

600 500

Ren. TRI, brick, air gap opened

400 300 200

Ren. TRI, brick, air gap closed

100 0 CF, material

CF heating, Moscow

CF heating, Kiev

CF heating, Tallinn

Figure. Carbon footprint for existing-and refurbished brick wall.


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14 000

Fossil energy, material

12 000

Fossil energy,, MJ/wall-m2/20 year

10 000

Fossil energy, heating, Moscow

8 000 6 000

Fossil energy, heating, Kiev

4 000 2 000


0 Existing cavity wall Ren. TRI, Cavity,air Ren. TRI, Cavity, gap opened air gap closed

Figure. Fossil energy consumption for existing-and refurbished cavity walls.

14000 Fossil energy, material

12000


10000 Fossil energy, heating, Moscow

8000 6000


4000


2000 0 Existing brick wall



Figure. Fossil energy consumption for existing-and refurbished brick walls. TRI – thermo reflective insulation.


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350


300 250


200

Ren. carbamide resin (60 mm cavity wall)

150

Existing wall, cavity with wool 100 Ren. carbamide resin (60 mm cavity with poor wool)

50 0 From material

From heating, Moscow

From heating, Kiev

From heating, Tallinn

Figure. Non renewable raw-material consumption for existing- and refurbished walls. Heating type for all location is gas.

Indoor air quality and acoustics Method decreases the impact of thermal radiation. Soundproof properties of the wall are improved. Also indoor air quality will improve.

Structural stability Structural stability does not change.

Fire safety Fire safety does not change.

Aesthetic quality Aesthetic quality does not change.

Effect on cultural heritage Increasing thermal and sound insulation, the view of exterior and interior remain unchanged.

Life cycle costs Principles of economic assessment:

The economical assessment covers only extra costs caused and energy cost to be saved by sustainable refurbishment compared with necessary refurbishment of facades. Possible improving in tightness and basic adjustment of heating system has been included in basic refurbishment.


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Economic assessment is based on the calculation of life cycle cost according to ISO 15686-5 Life Cycle Costing (LCC)4. LCC is a technique for estimating the cost of whole buildings, systems and/or building components and materials, and used for monitoring the occurred throughout the lifecycle. The results are presented in terms of net present values. This is calculated by summing up the activated costs in different years for present with present unit costs (without discount rate). The energy costs were calculated considering the realistic increase of costs. The cost information does not cover maintenance cost. Table - Refurbishment criteria and concepts for the concrete walls. Life Cycle Cost factors.

Type of life-cycle cost

Description

Building cost

Costs including all material, labour and sub costs caused by construction

Energy cost

Continual cost caused by the operation of the building including

Maintenance cost

-

Heating energy

-

Cooling energy

-

Electricity

Costs because of maintenance and renewing of components

Table - Examples of reference material and construction costs for insulation materials.

Other direct Material cost

construction costs

€/m2

€/m2

Soft rock wool 100 mm

7

8


10

8


13

8


15

8

Hard rock wool 100 mm

13

8


18

8


22

8

EPS (100S) 50 mm

19

8

EPS (100S) 100 mm

35

8

EPS (100S) 150 mm

49

8

EPS (100S) 200 mm

63

8

Insulation materials

4

ISO 15686-5 Life Cycle Costing.


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EPS (100S) 250 mm

75

8

Thermisol PlatinaRappari 50 mm

40

8


70

8


105

8


150

8

PUR foam with Al surface 120 mm

45

8


50

8


55

8

Table - Reference heating costs present value (year 2011). Heating mode

Heating cost, present value, Finland €/kWh

District heating

0,055

Electricity

0,09

Oil

0,105

Gas

0,08

Table - Material and construction costs for wind protection materials. Other direct Material cost

construction costs

€/m2

€/m2

Rockwool (WAB) 20 mm

9

8


13

8


19

10


24

10

PUR foam 40 mm with 9 mm gypsum board

30

7

PUR foam 70 mm with 9 mm gypsum board

50

8

Protection materials


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Table - Material and construction cost for facades. Other direct Material cost

construction costs

€/m2

€/m2

Polymer concrete board with fastening

120

35

Concrete board with fastening

70

30

Concrete with clinker plate and fastening

65

35

Natural stone slab with fastening

100

60

Masonry brick wall (85 mm)

70

50

Render with float and set

70

50

Facade material

Table - Labour cost index (Eichhammer et al.2009)

Austria

114

Belgium

106

Bulgaria

18

Croatia

32

Cyprus

91

Czech Republic

39

Germany

100

Denmark

122

Estonia

41

Greece

60

Spain

75

Finland

101

France

122

Hungary

32

Ireland

139

Italy

93

Lichtenstein

220

Lithuania

41

Luxembourg

168

Latvia

37

Malta

39

Netherlands

112

Norway

151

SUSREF Sustainable Refurbishment of Building Facades and External Walls Poland

38

Portugal

53

Romania

21

Sweden

127

cSlovenia

57

Slovakia

29

United Kingdom

141

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Table - Material cost index (Eichhammer et al.2009)

110

100

95

90

EU – Nordic countries

EU – Central Europe

EU – Southern Europe

Outside EU

Source: WI calculations based on BBR (2005)

Concept results Assessment of environmental impact and life cycle costs of refurbishment alternatives for walls and windows

The material costs include all costs of all materials/products. Direct construction cost include all costs onsite. Indirect costs are caused by extra works (for example renewing of upper floors) caused by extra thickness of wall structures. The results show the total acquisition, energy and life cycle cost within period of 20 years. Other direct Concepts

EKK1. Filling brick wall cavities with carbamide resin foam. EKK2. Thermoreflective multifoil outer insulation of brick wall with controllable ventilation air gap before insulation.

Material cost

Possible construction indirect cost costs

Investment cost all together

€/m2

€/m2

€/m2

€/m2

3

53

3

139

11

80

39

56


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Notes: All costs are without V.A.T. 1. Information about material cost (€/façade-m2) on different insulation thicknesses a EKK1: standard thickness 60mm – material cost 11€/m2 b EKK1: when thickness is 100mm – material cost 18€/m2 (other direct costs remain the same: 39€/m2) c EKK1: when thickness is 120mm – material cost 22€/m2 (other direct costs remain the same: 39€/m2) Concept EKK2: multi-foil insulation thickness is 10mm and it is not reasonable to change the thickness. 2. Information about other construction cost (€/façade-m2) a EKK1: standard thickness 60mm – other direct costs is 39€/m2 b EKK1: when thickness is 100mm – other direct costs remain the same: 39€/m2 c EKK1: when thickness is 120mm – other direct costs remain the same: 39€/m2 Concept EKK2: multi-foil insulation thickness is 10mm and it is not reasonable to change the thickness. 3. Information for calculation of indirect cost (€/façade-m2) a EKK1: standard thickness 60mm – indirect costs is 3€/m2 because of parapet construction; calculated for 5storey building (height 15m). b EKK1: when thickness 100mm – indirect costs remain the same 3€/m2 because of parapet construction and was calculated for 5-storey building (height 15m). c EKK1: when thickness 120mm – indirect costs remain the same 3€/m2 because of parapet construction and was calculated for 5-storey building (height 15m). 4. Material lambda values Material lambda values are listed in concept description tables except multi-foil insulation Triso Super 10 which data is given as thermal resistance: R=5.3 m2·K/W (U=0.19).


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Name: EKK

Moscow

SusRef

Concept: Thermo-reflective multi-foil outer insulation Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Basic

60 mm

Multiinsulated

193

152

21

€/m2

€/m2

€/m2


40

40

40


0

20

130

Heating cost/20 y

241

190

26

Life Cycle Cost

281

250

196

Mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS

Need for care and maintenance Any additional extra care or maintenance is not necessary.

Disturbance to the tenants and to the site Practically does not disturb. Some sound exists when drilling holes.

Buildability Method is quite new in Eastern-Europe region, but technology has created long time ago. For example in Denmark this method has been used nearly half a century. This kind of refurbishment work does not need very big qualification and two workers are enough to bring into effect this method.


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Pneumatic tank where carbamide resin foam will created at the site is quite common equipment. Other special tools are not required.


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10 Name of the concept – EKK2 - Thermo-reflective multi-foil outer insulation of brick wall with controllable ventilation air gap before insulation This solution is aimed at Eastern Europe buildings with clearly insufficient thermal insulation. The solution is quite effective to provide the needed improvement, but requires motivated clients as it is relatively costly and rather tedious to implement. The carbon footprint for the existing-and refurbished cavity wall can be significantly improved, as well as fossil energy savings. Indoor air quality and comfort will enhance, but ventilation upgrade is necessary. Workmanship needs to have proper qualification to realize the achievable benefits of the refurbishment method.

Application The suitable areas of application are as follows: -

-

BUILDING TYPES – Single- and multi-storey buildings. CURRENT STRUCTURE OF EXTERNAL WALL –Brick walls with air cavity or decayed wool insulation (D3.1 Table 3, type 4A). Also suitable for other good heat capacity wall types (concrete, stone etc). CLIMATIC ZONES – Dbf - cold, without dry season and with warm summer. Zone 3 - North European (Based on D3.1 document) and Zone 2 - Central (also Eastern) European countries.

Market potential The method is applicable on the big area in the Eastern-Europe. This refurbishment concept takes into account only 430mm sand-lime brick wall with decayed and sunken old mineral wool or just cavities without insulation. This type of brick wall is most represented in the Baltic countries, partially in Russia and Ukraine. Refurbishment method applied to the climatic zone 3, North European and partially to the zone 2, Central (Eastern) European countries. This refurbishment concept is intended to load-bearing brick wall which has air cavities or decayed and sunken old mineral wool between the brick layers. Wall thickness may varied 380…560mm and old insulation or cavity thickness is 60…140mm. Outer layer can be sand-lime or clay brick.

Reasoning Soviet-era building quality was very irregular. Mineral wool is used in the construction of the wall has lost its structural stability over time, sometimes a half-empty or heat insulating gaps in the insulation is not used at all. Heat loss is too big. In the hot summer the walls warms up and there are not enough time during the night to cool down the massive wall material. Indoor temperature rises uncomfortably high. Used mineral wool thermal resistance is about 40% worse than ordinary wool or foam insulation materials nowadays. The method reduces a building's energy consumption and increases the tightness of the structure. Operation can be done without the disassembly of a wall structure. Controllable air gap before thermal insulation allows improve the hydrothermal conditions in the wall and allow cooling down the massive brick wall in hot summer.


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Known problems related to refurbishment method We have to check out the condition of the external layer in every case to make a decision whether we can fasten new layers to the existing walls external layer or first we have to do strengthening or it is better to fasten the connecting anchors to the load bearing layer of the wall. Refurbishment costs will also depend on this fact. Thermo-reflective multi-foil insulation material is vapour proof; therefore the proper indoor microclimate is very important factor especially at early spring and late autumn time. Possible complexity to control the flap- or slide-valve (manual or automatic). Some maintenance needed. User experience is small and thermo-reflective multi-foil insulation material is quite expensive.



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Summary of the materials and layers thickness 1. Finishing layer (e.g. cement-chip board =1.7 W/m·K) – 10mm 2. Ventilated air gap between wooden or steel frame – 25 mm 3. Thermo-reflective multi-foil insulation, e.g. Triso-Super 10 (R=5.3 m2·K/W) 4. Manually controlled ventilation air gap using simple flap- or slide-valve – 25mm 5. Natural sand-lime brick – 120mm 6. Existing air gap or decayed and sunken wool insulation – 60mm 7. Sand-lime load bearing brick – 250mm 8. Finishing layer (with vapour barrier) – ~15mm

Description of working methods 1. Beforehand has to check out the condition of the external layer in every case to make a decision whether we can fasten new layers to the existing walls external layer or first we have to do strengthening or it is better to fasten the connecting anchors to the load bearing layer of the wall. 2. The levelled vertical wooden or steel frame has to fasten to the appropriate existing layer. 3. Install the flap- or slide-valve to the bottom area of the facade so that it can be controlled manually or automatically. 4. Install the thermo-reflective multi-foil insulation material on the vertical frame. Overlaps 5-10cm must be made on the supporting vertical frame using at least 14 mm stainless steel staples. All joints have to seal with special folium tape (e.g. Isodhesif) 5. Afterward the another vertical steel or wooden frame has to fasten so that there will ~25mm ventilated air gap. 6. Install the finishing layer, preferably with good heat absorption (cement-chip board or similar) 7. After that the window sill and reveals has to renew and frames have to seal. 8. Indoor ventilation has to be examined. If air exchange rate does not meet the requirements then ventilation system upgrade is necessary. Otherwise an effective vapour barrier at the inner layer of the wall is needed

Sealing of window and door frames Window sill and reveals has to renovate always when window remain to the existing layer. Window and door frames have to seal with appropriate tape.

Ventilation upgrades required Ventilation upgrade is required. Indoor air exchange rate should meet the requirements to avoid excessive moisture content in the wall structure.

Information about the performance values needed in the assessment U = 1.47 W/m2 K, in case of air cavity – existing construction U = 1.15 W/m2 K, in case of mineral wool – existing construction U = 1.30 W/m2 K, insulated with thermo-reflective multi-foil material (e.g. Triso-Super 10, 30mm) and air gap is opened. Old mineral wool is in the existing wall.


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U = 1.04 W/m2 K, insulated with thermo-reflective multi-foil material (e.g. Triso-Super 10, 30mm) and air gap is opened. Air cavities are in the existing wall. U = 0.16 W/m2 K, insulated with mineral wool (e.g. Triso-Super 10, 30mm) and air gap is closed. Both types of existing wall (old wool or cavity) Note: - thermal bridges 10% are taken into account in the existing insulation layer (60mm) and in the new layers (wooden frame). Material

Thickness, mm


Porosity

µ

[-]


[W/mk]

[-]

[kg/m3]

design

Sand-lime brick

120 / 250

2000

0.23

900

1.1

7

Cement (-lime) plaster

15

1800

0.31

1130

0.93

8

Mineral wool (old)

60

100

0.96

840

0.07

1.3

Thermoereflective multi-foil Triso-Super 10

10

R=5.3 m2·K/W

Cementchip board

10

1.7

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) In Northern European weather conditions, this kind of brick wall (sand-lime brick) is quite durable itself, but the physical performance is not good. Brick wall with cavity only or decayed and sunken mineral wool (existing wall) This wall passes through a quite considerable amount of moisture especially because of driving rain. The inner surface of the wall is cold at the winter time and frequently moist at the autumn and early spring time – it is a good condition for mould progress. This wall has also blowing through and acoustic problems. In the hot summer the walls warms up and there are not enough time during the night to cool down the massive wall material. Indoor temperature rises uncomfortably high. Brick wall with controllable ventilation air gap before thermo-reflective multi-foil insulation (refurbished wall) This method can improve the physical performance of the wall by innovative way. The 10mm thick multi-foil insulation has the same thermal characteristics than 200mm thick ordinary wool. Leaving controllable air gap between the existing wall and thermo-reflective insulation gives possibility to cool down the brick wall during the summer night time. At the heating seasons the air gap is closed except in


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the autumn and spring when sometimes we have to open the top side of the valve to taking out moisture which coming from inside of the room. It is necessary to install the humidity and temperature sensor in the air gap to control the necessity to change the valves position. Outside finishing layer does not make here any role for the physical performance – it is freely selectable. However, it is possible to use solar panels or heat exchangers on the outer layer of the wall. Approximate service life is 50 years.

Impact on energy demand for heating Construction heat loss is 193,0 kWh/m2 – 120mm sand-lime brick; 60mm air-cavity; 250mm sand-lime brick; 15mm plaster) Construction heat loss is 151,6 kWh/m2 – (120mm sand-lime brick; 60mm mineral wool; 250mm sandlime brick; 15mm plaster) Construction heat loss is 20,7 kWh/m2 – (cement-chip board 10mm; ventilated air gap 25mm; thermoreflective heat insulation (Triso-Super 10) 30mm; controllable air gap 25mm is closed ; 120mm sandlime brick; 60mm mineral wool; 250mm sand-lime brick; 15mm plaster) The heat loss values calculated based on Estonian normal-year average temperatures.

Impact on energy demand for cooling Effect is considerably high because we can cooling down a massive brick wall in hot summer when opening inner air gap at night time and closing at day time.

Impact on renewable energy use potential (using solar panels etc.) It is possible to use solar panels or heat exchangers on the outer layer of the wall.

Impact on daylight Does not have any important impact

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to the next assumptions: Life span is 20 year, For existing and refurbished wall only impact from heating energy is considered. Concept uses thermo reflective heat insulation (TRI), which environmental impact was not known. U-values were used as shown above. For heat flux and energy calculations heating degree days for different location, based on +18oC, have been used (see table below).


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For impact of heating energy main heating type is used. These presented in table below. kg CO2 equ/kWh

Fossil energy consumption,

Non renewable raw-material consumption, kg/kWh

Climatic zones (Dfb) Cities

HDD, +18oC

Heating energy type

Russia

Moscow

4654

gas

0.271

3.98

0.088

Ukraine

Kiev

3809

gas

0.271

3.1

0.088

Nordic

Tallinn

4562

gas

0.271

3.1

0.088

MJ/kWh

Cavity wall renovation with external thermo reflective insulation

165

145 125 Moscow

105

Kiev

85

Tallinn

65 45 25



165

Brick wall renovation with thermo reflective insulation

145 125 105

Moscow

85

Kiev

65

Tallinn

45 25 5

5 Ren. TRI, cavity, air gap opened

Ren. TRI, brick wall, air gap opened

Ren. TRI, Cavity, air gap closed

Ren. TRI, brick wall, air gap closed

Figure. Annual energy savings compared to the two type of existing wall (cavity and brick wall). The refurbishment concept considers open and closed air gaps. TRI - thermo reflective insulation.

Brick wall renovation with external thermo reflective insulation

905

905

805

805

705 605 505

Moscow

405

Kiev

305

Tallinn

205 105



Cavity wall renovation with external thermo reflective insulation 705 605 505

Moscow

405

Kiev

305

Tallinn

205 105 5

5 Ren with TRI, air gap opened

Ren. With TRI, air gap closed

Ren. With TRI, air gap opened

Ren. With TRI, air gap closed

Figure. Carbon footprint savings compared to the two types of existing walls (cavity and brick wall).TRI – thermo reflective insulation


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Brick wall renovation with external thermo reflective insulation

Cavity wall renovation with external thermo reflective insulation

14 000

14 000

12 000

10 000 8 000

Moscow

6 000

Kiev

4 000

Tallinn


Fossil energy savings, MJ/wall-m 2/20 year

12 000

2 000

10 000 8 000

Moscow

6 000

Kiev

4 000

Tallinn

2 000

0 Ren. TRI, air gap opened

Ren. TRI, air gap closed

0 Ren. TRI, air gap opened

Ren. TRI, air gap closed

Figure. Fossil energy savings compared to the two types of existing walls (cavity and brick wall).TRI – thermo reflective insulation

1000 Existing cavity wall

kg CO2 eq /m2/20 year

900 800 700 600

Ren. TRI, Cavity, air gap opened Ren. TRI, Cavity, air gap closed

500 400 300 200 100 0 CF, material CF heating, CF heating, CF heating, Moscow Kiev Tallinn

Figure. Carbon footprint for the existing-and refurbished cavity wall.


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1000 kg CO2 eq /m2/20 year

900 800 700

Existing brick wall

600 500


400 300 200


100 0 CF, material

CF heating, Moscow

CF heating, Kiev

CF heating, Tallinn

Figure. Carbon footprint for existing-and refurbished brick wall.

Fossil energy, material

14 000 12 000


10 000

Fossil energy, heating, Moscow

8 000 6 000


4 000 2 000


0 Existing cavity wall Ren. TRI, Cavity,air Ren. TRI, Cavity, gap opened air gap closed

Figure. Fossil energy consumption for existing-and refurbished cavity walls.


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14000 Fossil energy, material

12000


10000 Fossil energy, heating, Moscow

8000 6000


4000


2000 0 Existing brick wall



Figure. Fossil energy consumption for existing-and refurbished brick walls. TRI – thermo reflective insulation.

Non renewable raw material, kg/wall-m2/2o year

350 300 250 From heating, Moscow From heating, Kiev

200 150 100 50 0 Existing cavity wall Ren. TRI, Cavity,air Ren. TRI, Cavity, gap opened air gap closed

Figure. Non renewable raw material consumption for existing and refurbished cavity wall. TRI – thermo reflective insulation.


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350

Non renewable raw material, kg/wall-m2/2o year

300 250

From heating, Moscow

200

From heating, Kiev

150

From heating, Tallinn

100 50 0 Existing brick wall Ren. TRI, brick, air Ren. TRI, brick, air gap opened gap closed

Figure. Non renewable raw material consumption for existing and refurbished brick wall. TRI – thermo reflective insulation.

Indoor air quality and acoustics Method decreases significantly the impact of thermal radiation. Indoor air quality and comfort will enhance, but ventilation upgrade is necessary. Soundproof properties of the wall are improved.

Structural stability Overall building structural stability does not change but stability of external brick-layer has to be examined.

Fire safety Choice of materials used should always be tested under the fire safety requirements.

Aesthetic quality Aesthetic quality will change. The exterior cladding material is freely selectable.

Effect on cultural heritage The method can be used in buildings where are allowed to change the facade. It is necessary to consult local planning conditions.


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Life cycle costs Name: EKK

Moscow

SusRef

Concept: Thermo-reflective multi-foil outer insulation Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Basic

60 mm

Multiinsulated

193

152

21

€/m2

€/m2

€/m2


40

40

40


0

20

130

Heating cost/20 y

241

190

26

Life Cycle Cost

281

250

196

Mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS

Need for care and maintenance Flap- or slide-valve needs some minor maintenance approximately every 5 years. Maintenance for finishing-boards surfaces is about 20…30 years; maintenance of jointing is 10 years. Control cycle 5 years.


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Disturbance to the tenants and to the site Refurbishment is fairly time-consuming. Scaffolding with protection screen is required. Some disturbance to the tenants will exist.

Buildability This refurbishment method without controllable air gap is a common practice throughout EasternEurope region. Controllable air gap with flap- or slide-valves need further development for reliability issues. This kind of refurbishment work does need some qualification, experience and accuracy especially when installing controllable air-gap system.


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11 Name of the concept – Exterior refurbishment of wooden frame walls - with a flex system board insulation This concept has a strait forward refurbishment procedure and is fairly easy to implement in particular in the case of single story buildings and moderate thickness of the additional insulation. A continuous insulation layer across the wall eliminates the thermal bridges, resulting in a considerably warmer and drier original wall construction, with a reduced risk for moisture damage. As the refurbishing the exterior walls increases air tightness of the envelope, fresh air inlets are required and installation of a balanced ventilation system is recommended. Along with this concept, when equipped with a balanced ventilation system with heat recovery, the house also takes benefit of the heat in the exhaust air. The concept is most efficient in the refurbishments to fairly thick additional insulation with the buildings in fairly cold climates, and the life cycle costs are hard to recover in the middle Europe.

Application Building types – detached and terraced house Current structure of external wall – wooden frame wall Climatic zones – Cfb- Oceanic climate (Bergen) Dfa-Continental climate (Munich) Dfb- Humid, continental climate (Oslo, Helsinki, Berlin) Dfc—Cold, without dry season and with cold summer. (Tampere, North European)

Market potential The wooden frame wall house is a conventional building in the northern part of Europe, with over 1,3 million buildings built before 1980, only in the Nordic countries. Also in the central part of Europe, the Benelux countries, Germany and Austria, almost 2,5 million buildings with wooden frame walls from 1980 or earlier are to be found.

Reasoning When an owner has a wish of reducing the energy demand, refurbishment of exterior walls always must be viewed in the context of other measures to reduce heat loss, such as refurbishment of roof or floor construction, as well as repair and replacement of bad windows with high U-values. Especially important is to stop the air leakage in older houses, often occurring along the transition between wall and floor/loft joist frame, around windows and doors. In some cases, such measures provide substantially improved thermal comfort and reduced heating demand. When evaluating refurbishment method and insulation thickness, one must also take into account the climate of the location and structure of the wall. Exterior insulation as a refurbishment method is favorable, achieving both low heat loss, a better thermal comfort and decreases the risk of low local indoor temperature and high relative humidity. A continuous


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insulation layer across the wall eliminates the thermal bridges, resulting in a considerably warmer and drier original wall construction, with a reduced risk for moisture damage.

Known problems related to refurbishment method By increasing the thickness of the wall, setting up a vapour barrier or a new wind barrier when refurbishing houses, the air tightness of the building will increase. The air change in the house can thereby decrease, especially in houses with natural or exhaust ventilation system, leading to a poor indoor climate with moisture damages, health problems and increased risks for developing asthma and allergy as a result. By installing balanced ventilation this problem can be avoided.


19 mm

Wooden cladding

25 mm

Air gap

2 mm

Impregnated building paper

100 mm

Woodframe with mineral wool cc 600

0,1 mm

Vapour barrier

13 mm

Gypsum board

U-value: 0,42 W/m2K



Summary of the materials and layers thickness 19mm

Wooden cladding

25mm

Air gap

100/200 mm Rockwool Flex System Board 1mm

Rockwool Wind Barrier

100mm

Wood frame with mineral wool cc 600

0,1mm

Vapour Barrier

13mm

Gypsum Board

U-value (100mm): 0,19 W/m2K U-value (200mm): 0,12 W/m2K

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Description of working methods 1. Strip the original wall, including outer cladding, laths and the old wind barrier. 2. Inspect the condition of the original insulation. When needed, replace damaged insulation boards. 3. Mount the new wind barrier on top of the old insulation. 4. Mount the Rockwool Flex System board with screw and discs. 5. Create an air gap by vertical and horizontal lathing mounted with a Flex System screws. The vertical laths should be mounted with a maximum cc 600 mm. The screws should not have a cc over 800 mm. To avoid wrench in the lath, the screws should be placed away from the centre line of the lath but minimum 32 mm from the edge. 6. Mount the chosen outer cladding on the horizontal laths according to the suppliers’ recommendations, but the weight may not excide 25 kg/m2.

Sealing of window and door frames Keeping the windows and doors in their original positions will affects a number of issues and should be considered carefully. You must bear in mind aspects relating to moisture, thermal insulation and architectural design. In order to avoid thermal bridges, and thereby eliminate unnecessary heat loss, the window should be positioned roughly in line with the layer of thermal insulation. As a general rule, the window should be placed so that the turned-up edge of the weatherboard flashing is just outside the wind barrier. This minimizes heat loss, makes it easier to seal against rain and minimizes the risk of damage due to moisture. The external casing and sealing must prevent rain and wind from penetrating through the wall via the joint between window and wall. It must also be possible for the window and joint to dry out, so that materials that become damp can quickly dry out again. The joint must be sufficiently airtight on both the cold and warm sides to prevent through-going air leaks and convection within the joint insulation. This is done by the following from the outside and in: Elastic sealent A neoprene tube Insulation Moisture barrier The gap between the frame and the window opening should be insulated to its full depth, for instance using strips of mineral wool or similar, which can be pushed loosely into the space from the inside. The insulation must not be pushed in so hard that the external seal is damaged or the frame or the trim is pushed inwards. The insulation only provides a very poor wind barrier, and cannot be used in place of other separate external and internal air seals. This is true both of mineral wool and other fibrous materials that can be used to provide thermal insulation in the space between the window frame and the wall. The internal seal is important, and must be executed with care. Its purpose is to provide an air seal and prevent external draughts entering the room. It is also intended to prevent moist air from the inside penetrating through to the external seal, where it would cool down and release moisture in the form of condensation.


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The internal seal should either be produced by pressing the moisture barrier against the trim using the interior mouldings, nailed every 200 mm, by using elastic sealant. Elastic sealants are particularly suitable for wet rooms such as bathrooms and utility rooms.

Ventilation upgrades required When refurbishing the exterior walls it is important to be aware of the increased air tightness of the envelope. Fresh air inlets are required and installation of a balanced ventilation system is recommended. With a balanced ventilation system with heat recovery, the house also takes benefit of the heat in the exhaust air.


Thick ness, mm


Porosity [-]

[Kg/m3]


[W/mk]

[-]

dry

µdry

Wooden cladding

19

390

0,75

1600

0,13

108

Rockwool Wind barrier

1

130

0,001

1500

3

17

Rockwool flex system board

100...20 0

60

0,95

850

0,035

1,3

Woodframe with mineral wool

100

60

0,95

850

0,04

1,3

Vapour barrier

1

130

0,001

2200

2,2

70000

Gypsum board

12,5

850

0,65

850

0,2

8,3


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Manufacturer declare that the approval of -value is calculated in accordance with European standards and the buildings life time of 50 years. The main components in rock wool are stone and air which do not deteriorate. The phenolic resin, used as a binder will get stiffer but has no effect on the product in a closed construction. There is a need of maintenance of the exterior cladding, this is highly depending on the climate and orientation of the walls and can therefore differ in intervals.

Criteria

Description

Values

Unit

Thermal performance


0,19

W/(m2K)

Thermal bridge effect Conclusion Moisture performance

Good performance

Annual moisture accumulation -0,488

kg/m2/year


h/year

T95% Risk for mould, corrosion T>0 C, RH>80%

33

158

Risk for condensation, algae, decay 16 T>0 C, RH>95%

Indoor climate

Overall conclusion

Actions

h/year

h/year

Conclusion

Good Performance


18,9

Conclusion


C


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Impact on energy demand for heating A whole-year building demand of heating has been calculated on a inhabited two storey detached house (160 m2 ), in accordance with D 3.2. The impact on the energy demand for heating is highly dependant on the climate, though the relative saving are corresponding, with a slightly higher reduction in the colder climates. A refurbishment with 100 mm exterior insulation will decrease the heating load with approximately 16 % respectively 21% for 200 mm extra insulation, see table and figure. Climate

TOBB TOBB_100 TOBB_200 [kWh/m2a] [kWh/m2a] [kWh/m2a]

TOBB

TOBB_100 TOBB_200

Oslo

115

97

91

84%

79%

Bergen

109

91

85

83%

78%

Helsinki

127

106

100

84%

79%

Tampere

135

113

106

84%

79%

Berlin

87

72

68

83%

78%

Munich

94

78

72

82%

77%

Impact on energy demand for cooling Use of cooling is unconventional in the northern part of Europe. Although when simulating the detached house, a need for cooling do appear even in the cold climates. The refurbishment do not influence the cooling load, see table and figure. Although a slight dissimilarity in the cooling load can be distinguished between the two storeys where the upper floor (zone 2) has a greater need of cooling during the summer. Climate

TOBB

TOBB_100

TOBB_200

[kWh/m2a]

[kWh/m2a]

[kWh/m2a]

Oslo

5

5

5

Bergen

2

2

2

Helsinki

5

4

4

Tampere

5

5

5

Berlin

9

8

8

Munich

8

8

8


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Heating and cooling demand for a detached house in Oslo climate


Impact on daylight If the position of the windows will be unchanged, the extra insulation will act as an outdoor fixed sun shade. This will result in a minor effect on the daylight in the house.

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, Refurbishment concepts considers all materials used and two insulation levels 100 mm and 200 mm additional rockwool. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 0.42 W/m2 K, U-value for the concept with 100 mm additional insulation is 0.19 W/m2 K U-value for 200 mm additional insulation is 0.12 W/m2 K. For heat flux and energy calculations heating degree days for different location, based on +18 oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below.


142 (232) kg CO2 equ./kWh


Electricity, Nordel

0.167

Not known

Not known

3738

Gas

0.271

3.98

0.088

Oslo

4172

Electricity, Nordel

0.167

Not known

Not known

Helsinki

4712

District heat

0.210

3.1

0.103

Berlin

3155

Gas

0.271

3.98

0.088

Cities

HDD, +18oC

Heating energy type

Bergen

3998

Munich



40,00 35,00 30,00 Bergen

25,00

Munich 20,00

Oslo

15,00

Helsinki Berlin

10,00 5,00 0

50

100

150

200




250


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2 100

Fossil energy, savings, MJ/wall-m2/20 year

1 900 1 700 1 500 Munich 1 300

Helsinki Berlin

1 100 900 700 0

50

100

150

200

250

Thickness of additional insulation layer, mm

Figure. Fossil energy savings compared to the existing wall. 55

Non-renewable raw material savings, kg/wall-m2/20 year

50 45 40 35 30

Munich

25

Helsinki Berlin

20 15 10 5 0

50

100

150

200

250

Thickness of additional insulation layer, mm



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kg CO2 eqv/wall-m2/20 year

250 CF heating

200

CF, material

150

100

50

0

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating use. Heating type for Helsinki was district heat, for Munich and Berlin it was gas and for Oslo and Bergen it was direct electricity. 3500 3000

Fossil energy, MJ/m2/20 year

2500

CF heating CF, material

2000 1500 1000 500 0

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for Helsinki was district heat for all other locations it was gas.


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Non-renewable raw-material, kg/wall-m2/20 year

120 100 CF heating 80

CF, material

60 40 20 0

Figure. Non renewable raw-material consumption for existing- and refurbished walls. Information about rawmaterial consumption for direct electricity used in Norway was missing

Indoor air quality and acoustics The indoor air quality will be affected depending on the impact on air leakage and the chosen ventilation system for the building, see further “Ventilation upgrades required”. Although the wind barrier increases the air tightness, the joints and penetration, as window, doors and pipes is as important for the airtightness as the wall itself. An air leakage test and ventilation rate should be examined before and after the refurbishment. The surface temperature of the wall increases and therefore improves the temperature asymmetry. An external insulation may reduce the sound transmission although other parts of the envelop will decrease the effect.

Structural stability The original building must be able to handle the extra weight of 100 or 200 mm insulation. This is a challenge when the insulation layer increases. If the building is multiple storeys, the screws will not be able to manage the weight, and the frequency of screws will increase, or replaced with standing joist, resulting in more thermal bridges and higher U-value on the wall.

Fire safety The air cavity can cause a fire spread depending on the insulation. The mineral wool has a fire class of A1, which means it is non-combustible and do not contribute to fire.

Aesthetic quality When refurbishing the exterior wall, the house´s appearance can change. To avoid undesirable changes the eaves, level differences between the house wall and the foundation must be taken in account. The location of the windows and doors in relation to the wall must also be taken into account, whereby the impact on the aesthetics will be greater the thicker the refurbishment layer is. This can be avoided by


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repositioning them further out in the construction and thereby also preventing considerable thermal bridges. Furthermore, one must take into account the surrounding buildings.

Effect on cultural heritage For listed buildings refurbishment projects should be in accordance with the cultural heritage act and approved by the heritage authority.

Life cycle costs Name: TOBB

Helsinki

SusRef


Basic

100 mm

200 mm

47

21

14

€/m2

€/m2

€/m2


90

90

90


0

20

35

65

29

19

155

139

144




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Name: TOBB

Oslo

SusRef

Concept: ETICS applied to solid panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Basic

100 mm

200 mm

42

19

12

€/m2

€/m2

€/m2

100

100

100

0

25

40

84

38

24

184

163

164


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Name: TOBB

Munich

SusRef


Basic

100 mm

200 mm

38

17

11

€/m2

€/m2

€/m2

100

100

100

0

25

40

48

21

14

148

146

154


149 (232)

Name: TOBB

Berlin

SusRef


Basic

100 mm

200 mm

32

14

9

€/m2

€/m2

€/m2

100

100

100

0

25

40

40

18

11

140

143

151


150 (232)

Need for care and maintenance Care should be taken during construction to ensure that the flex system board keeps intact and no thermal bridges are created. Repainting on the wooden outer cladding is usually needed.

Disturbance to the tenants and to the site Since the tenants will be living in the their dwelling during the whole project it`s important that the construction work is carried out with as little burden as possible for the tenants. With this kind of project the tenants will experience some noise for outdoor activities. In addition to the refurbishment of the walls we also changed the windows in every dwelling and installed a balanced ventilation system. To conduct this work the contractor needed about four days inside the dwelling with the disturbance this is for the tenants.

Buildability Refurbishment with mineral wool on the exterior wall is a conventional measure for decreasing the heat loss in houses in Europe. This technique does not differ much from the traditional refurbishments and will therefore be a competitive alternative to the conventional choices.


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12 Concept number 1 by ONEKA – Transparent insulation The innovation of this concept combines the properties of good optical transmission with good thermal insulation. Transparent insulation (TIM) improves the thermal performance of the exterior wall not only by reducing the transmission losses but also by enabling solar gains. The system reduces energy demand through better U-values, by acting on the wall or on the windows. It increases solar gains through the wall thus enabling renewable solar energy. Depending on the amount of solar radiation and the external temperature the transmission loss is reduced or the heat transfer is reversed. The transparent insulation acts as heating system. This system is not suitable for climates where cooling is demanded because it increases solar gains through the wall, but it is quite plausible in more temperate areas.

Application The concept is suitable for the following application areas: -

BUILDING TYPES - single/detached family houses and multi-storey buildings. CURRENT STRUCTURE OF EXTERNAL WALL - cavity brick walls: Plaster (15 mm), inner leaf of hollow brick (70 mm), cavity (30-40 mm, insulation in some cases (30 mm), outer leaf of solid or perforated brick (115 mm) CLIMATIC ZONES – Csa - temperature with dry, hot summer – Cfb - cold, without dry season and with warm summer

Market potential The double skin external wall is the most common façade for residential buildings since 1950 (i.e: Spain). Adding thermal insulation to external wall were not required by Rules and Regulations until 1979, that is why the market potential building stock is the one built before this date. In any case, this refurbishment solution can be equally used for any building up to now.

Reasoning This system is eligible for new buildings optimized for solar gains as well as for the improvement and renovation of existing buildings, to provide improved heat insulation, solar gains and comfortable light. There are two variants of Transparent Insulated Solar Walls: 1. Solar Wall as heat storage: Integrated in a façade insulation system it does not only reduce thermal losses by insulation, but heats the building as well by using sun energy. (OPAQUE) 2. Solar Wall as day lighting system: this system saves electrical power and permits daylight without glare. (TRANSLUCENT) There are also different materials of transparent insulation, but honeycomb has larger flexibility for the application, according to its orientation.

1. SOLAR WALL AS HEAT STORAGE TIM combines the properties of good optical transmission (described by the total solar transmittance) and good thermal insulation (describes by the heat loss coefficient of U-value).


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The principle: Solar rays cross the light permeable Transparent Insulation module and hit the dark massive wall. Here the solar power is converted into heat and stored in the wall, which conducts the heat with a time delay of several hours into the interior.

Functional principle of solar wall heating

Transparent insulation (TIM) improves the thermal performance of the exterior wall not only by reducing the transmission losses but also by enabling solar gains. The solar radiation on the wall is transmitted through the insulation material and absorbed at the exterior surface of the inner shell of the wall and converted to heat. The insulation material in front ensures that a large part of the gained heat is transferred to the inner shell of the wall. Depending on the amount of solar radiation and the external temperature the transmission loss is reduced or the heat transfer is reversed. The transparent insulation acts as heating system. The inner shell works as a storage system and controls the time delay of the heat transfer from outside to inside (depending on its thermal capacity).

Unnecessary fear of overheating In wintertime, when the sun position is low during the day, the rays penetrate almost completely the transparent insulation structure and reach the wall and heats up the whole skin layer. However, during summer when the sun is high, the energy input is very much reduced due to the solar wall principle. In fact, the honeycomb structure shades themselves for high solar altitude. Active solar protection is just need usually for very large glazed areas or for east or west orientation.


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2. SOLAR WALL AS DAY LIGHTING SYSTEM Honeycombs in transparent surface

Enhancements of TIM: - Reduces direct daylight glare; homogeneous illumination - Daylight is distributed throughout interior with no glare - There are no hard cast shadows

Known problems related to refurbishment method Most common refurbishment problems related to transparent insulation concept: -

In most regions shading devices are necessary for summer. Active solar protection is needed usually for very large glazed areas or for east or west oriented walls

-

High investment costs.

-

Needs approval by the fire department.

-

Gains can only be used in suitable building types (evening use).

-

Production is very limited: it’s not yet a regular building product; small market.


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Cross section figure of the existing external wall Based on deliverable D 3.1 the envelopes studied in South European Countries are the following:

(1930’s-1950’s)

(1950’s-1980’s)

(1950’s-1980’s)

(since 1980’s)


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Cross section figure of the refurbishment concept The Transparent Insulation concept, as heat storage, applied to the F3 external wall. The solution is the same to the rest of the cases:

F3 – Cavity brick wall

Transparent Insulation + F3 solution


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Summary of the materials and layers thickness Description of the Transparent Insulation Materials 1. Elements that allow a good radiation transmission and have good insulation properties. 2. Optimal solar energy index. 3. Light transmission and transparency. 4. Good insulation characteristics: low thermal conductivity value and reduction of the convection effect.

The insulation consists of many transparent tubules side by side. In front of the tubules a translucent covering of the insulation. The rays of the sun cross the transparent insulation reaching the façade and goes through an external insulating layer up to a black absorbing plate in which it is turned into heat. Because of the heat insulation the warmed-up absorbing level does not radiate his warmth outside but towards the rear walls, increasing their temperature. Transparent Insulation applies to refurbishment concept cross section below:

Transparent insulation 1. glass – 6 mm 2. diffusing cloth – 1 mm 3. spacer and sealant – equal to insulation 4. transparent insulation material: small-celled plastic honeycomb and capillary structure – 60/120 mm


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5. glass – 6 mm

External wall 1. perforated face brick – 115 mm 2. cavity – 30/40 mm 3. hollow brick – 70 mm 4. cement or cement-lime plaster – 15mm

Description of working methods 1. Beforehand has to check out the condition of the external layer in every case to make a decision whether we can fasten new layers to the existing walls external layer or first we have to do strengthening or it is better to fasten the connecting anchors to the load bearing layer of the wall. 2. When renovating façade the surface has to be clean and dry. Existing exterior paint and mortar layer is scraped off, it can be made by hand or using mechanical means. Possible surface irregularities and minimum deviations can be removed with rough sand paper attached to a float. 3. Water resistant mortar is applied to the whole façade surface. Primer must be thoroughly dried out (min. 24 hours) before panel application. While drying out, the façade must be protected against strong sunlight, rain and wind. At low temperatures and high humidity, the mortar will take longer to dry. 4. There are two supporting methods for TIM panel application: mechanical supports or glue fixing. - Glue fixing: a glue layer is applied on the external mortar layer for honeycombing capillary structure support. Before applying the first layer of adhesive, all corners of the building have to be smooth and reinforced - Mechanical support: precast Transparent Insulation panels are supported by a metal frame (steel or aluminium) which is fixed to the bearing structure of the existing building. A hole is drilled by a crown drill through which stainless elements are places to support the honeycomb insulation panels. 5. Install panels 6. After that the window sill and reveals has to renew and frames have to seal.


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Sealing of window and door frames

External sealant Window sill and reveals have to be renovated Window and door frames have to seal with appropriate tape.

Intermediate sealant The gap around the frame (window and door jambs) is sealed with elastic polyurethane foam. Sealing should be homogenous and air-tight.

Internal sealant The façade refurbishment is an outside intervention, TIM as solar wall heat storage, so its not necessary to act in the interior.


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Ventilation upgrades required The method itself does not need ventilation upgrade so there is no influence.

Information about the performance values needed in the assessment U-value of the total refurbishmed external wall: UF3+TIM = 0,48 W/m2ºC Properties Material

Thickness, mm

Bulk density

Porosity [-]

[Kg/m3]


dry

[W/mk]

TIM panel

60…120

RTIM panel = 1,2 m2ºC/mW

Air cavity (optional)

20….100

RTIM air cavity = 0,125 m2ºC/mW

perforated face brick

115

air cavity

50

hollow brick

70

630

-

cement lime plaster

15

2100

-

1020

-

1000

µdry [-]

0,595

10

1000

0,182

10

1000

1,8

10

Rair = 0,18 m2ºC/mW


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Under normal weather conditions and with correct maintenance, the glass has good durability and in fact it does not have problems of moisture so the service life must be long enough.

Transparent Insulation Criteria Thermal performance

Description Transmission coefficient

Values

Unit W/(m2K)


Annual moisture accumulation Risk for frost damage

Good performance kg/m2/year h/year

T95% Risk for mould, corrosion

h/year

T>0 C, RH>80% Risk for condensation, algae, decay

h/year

T>0 C, RH>95% Conclusion Indoor climate

Just sufficient

Lowest indoor surface temperature Conclusion

C Very good performance

Overall conclusion

Actions

Impact on energy demand for heating Reduces energy demand through better U-values, by acting on the wall or on the windows. Increase solar gains through the wall.

Impact on energy demand for cooling This system turns out to be harmful to climates where cooling is demanded because it increases solar gains through the wall.


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Impact on daylight Using TIM as lighting system, daylight is distributed through the interior with no glare. Transparent Insulation with different light scattering qualities and added solar protection ensures that an optimum quality and quantity of light and energy is entering the building. The daylight systems have an excellent thermal resistance and provide a high insulation value.

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, For existing and refurbished wall only impact from heating energy is considered. Concept uses transparent insulation, which environmental impact was not known. U-value for existing wall is 1,16 W/m2 K, U-value for the transparent insulation with glass layers is 0.58 W/m2 K For heat flux and energy calculations heating degree days based on +18oC, have been used (see table below). For impact of heating energy main heating type is used. These presented in table below. HDD,

kg CO2 eq/kWh



Cities

+18oC

Heating energy type

Barcelona

1419

Gas

0.271

3.98

0.088

London

2868

gas

0.271

3.98

0.088


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500

Carbon footprint, kg CO2 eq /wall-m2/20 year

450 400

Existing wall

350 300 250

Ren.2, transparent insulation (glass capillary layer)

200 150 100 50 0 CF, material

CF heating, Barcelona

CF heating, London

Figure. Carbon footprint for existing-and refurbished walls. Heating type for both cases is gas. Impact from used materials was not known.

7 000


6 000 Existing wall

5 000 4 000

Ren.2, transparent insulation (glass capillary layer)

3 000 2 000 1 000 0 from material

from heating, Barcelona

from heating, London

Figure. Fossil energy consumption for existing-and refurbished walls. Heating type for both cases is gas. Impact from used materials was not known.


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160


140

Existing wall

120 100

Ren.2, transparent insulation (glass, capillary layer)

80 60 40 20 0 from material

from heating, Barcelona

from heating, London

Figure. Non renewable raw material consumption for existing-and refurbished walls. Heating type for both cases is gas. Impact from used materials was not known.

Indoor air quality and acoustics Generally the indoor air quality will not be affected. However, the sealing of window and door frames guaranties that water, air and humidity are not coming inside. The exterior structure reduces outdoor noise.

Structural stability Structural stability should be studied individually on each building. The increase of load on the existing wall is going to be minimal because it is going to be mainly supported by the principal structure of the building.

Fire safety According to local regulations, it needs approval by the fire department. The expose face of the panel is glass, which protects the inner insulation material, so it makes no fire risk.

Aesthetic quality It is necessary to study carefully the encounter of the external wall with windows, doors, eaves, balconies… due to the fact that the thickness of the façade has been increased. It can be solved with additional elements such as rabbet, edging profile.

Effect on cultural heritage If used to renovate an external wall currently using the same material as the original then it is acceptable. If the external covers up some different existing material then it is necessary to consult local planning conditions.


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This system will always modify the external image of the building

Life cycle costs

Name: Oneka

London

SusRef

Concept: ETICS applied to solid panel Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Transparent insulation Heating energy (kWh/m2/a)

Basic honeycomb

glass capillary layer aerogel

80

36

40

€/m2

€/m2

€/m2


90

90

90

90


0

25

25

50

Heating cost/20 y

160

72

80

34

Life Cycle Cost

250

187

195

174

ECONOMICAL EFFECTS

17


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Need for care and maintenance Care should be taken during construction to ensure that the transparent insulation panels’ joins are well fixed to the surface as this will encourage the attachment and avoid water penetration.

Disturbance to the tenants and to the site Entire structure of external wall remains, so there should be no physical disturbance to tenants, only noise pollution.

Buildability The method is quite new and the technology is still been developing.


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13 Concept number 1 by SGG – SGG 1: External insulation of solid rubble stone wall with vapour-open natural insulation material and ventilated timber cladding This concept is highly suited for cultural heritage conservation of very old buildings where very few refurbishment methods have been developed until now. As the method is applied on the outer surface, the appearance will change, but the building can conserved for occupation. While the external appearance is altered completely, the method is only suitable for buildings where the external appearance is not of historic importance. The heating cost will drop to approximately one tenth with the implementation of this concept, so the use of the refurbished becomes feasible. The environmental sustainability is good as the materials used have a low carbon and resource-use footprint and can be reused, reprocessed or recycled with low impacts at the end of their life.


Building Types – single and multi-storey buildings Current structure of external wall – Solid thick wall (400 – 1000mm) built with two faces of stonework. No insulation. Climate zone - Zone 2 (Cfbw - mild, wet, windy)

Market potential Zone 1 (Southern): 11.6million dwellings Zone 2 (Central):15.6 million dwellings Zone 3 (Northern): 1.03 million dwellings (Derived from IMPRO: Dwellings with solid masonry or concrete walls, by date unlikely to have cavity or insulation)

Reasoning These thick walls (400mm – 1000mm) are built up with two faces of stonework with loose rubble packed between them to hold the external stone faces vertical. Some walls also have limited amounts of earth or mortar fill. The inner face was plastered. The outer face may be rendered or pointed. Significant air voids of irregular shape occur in the wall and through-stones are distributed all over wall, and around openings. These mean that cold bridges and actual air currents occur. Rain driven between stones can fall in the voids and land on a through-stone, emerging inside or outside. The method of insulating removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. The work can be carried out from outside without disturbing occupants. The materials used have a low carbon and resource-use footprint and can be reused, reprocessed or recycled with low impacts at the end of their life.

Known problems relating to refurbishment method The overall build-up is thick (175mm), usually necessitating roof eaves and verges to be extended. Cills must be removed and replaced with much deeper cills with a thermal break. Service entries (gas, air supply or extract, balanced flues, drainage pipework etc.) need to be disconnected and adapted or relocated.


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Reveals to doors and windows cannot be insulated with the same method unless it is acceptable that the opening is much reduced in size. In gable wall with chimney, the insulation is not carried up around the chimney. If roof, doors and windows are to be replaced at the same time as the external walls are clad, these can be extended/relocated to suit the insulation at very little additional cost and without significant reduction in opening size. The biodegradable insulation and cladding materials cannot continue down to ground level so the lowest part of the wall must be insulated using a different non-rotting material The external appearance (rendered or pointed masonry) is completely altered.



600 mm rubble walling with cement/sand pointing 15 mm internal cement/sand basecoat and gypsum skim plaster

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Cross section of the refurbishment concept 1. 25mm sawn timber boards 2. Air cavity with 25mm x 50mm horizontal battens at 600 - 750 centres 3. Air cavity with 25mm x 50mm vertical battens at 600 centres 4. Breather membrane wind screen 5. 100mm natural sheep's wool insulation quilt between 50mm x 100mm timber studs at 600mm centres 6. 25mm cement/sand render with pebbledash finish (existing) 7. 600mm rubble stone wall (existing) 8. 15mm internal plaster of basecoat & gypsum skim (existing)

Summary of the materials and layer thickness Renovation material list and application techniques (applies to refurbishment cross section shown above) 1. Cladding of sawn or planed timber (durable species eg Larch) – 25mm thick, max 10mm wide, buttjointed. Each board fixed with 2 ring-shanked stainless steel posidrive screws 25mm in from board edge 2. Open ventilation layer formed by horizontal timber rails 25mm x 50mm at max. 750mm centres 3. Open ventilation layer formed by vertical timber rails 25mm x 50mm at 600mm centres 4.

Vapour-open breather membrane eg Tyvek Housewrap turned round and sealed at all laps and edges as wind barrier

5. 100mm natural sheep’s wool insulation quilt (85% wool max 15% polyester fibre) between

Vertical timber studs 50 x 100mm at 600mm centres screwed to masonry wall


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Sealing of window and door frames and other openings If existing windows and doors are retained, external reveal insulation (in a thinner insulation material) must be sealed to frames. Existing cills need replacing. Service entries must be sealed.

Description of working method 1. Check condition and verticality of existing wall Check projection of roof at eaves & verges Check margin available at reveals for insulation Note cills and other abutment/attachment/projections forming cold bridges Decide strategy on chimneys (remove redundant chimneys and close roof? Stop insulation at base of chimney and provide cover flashing to insulation?) Check ground levels and possibility of installing land drain 2. Strip eaves & verges and extend, reslate Remove cills & hack off render from existing reveals; fix new cill brackets Remove rainwater goods, alter service pipework etc. Excavate trench and lay land drains 3. Fix base insulation, stainless steel expanded metal lath, and render Fix vertical wall studs including for packing them out at out-of-vertical walls Fill between studs with insulating quilt and cover with windscreen breather membrane, sealed at laps and all edges and openings. Carry membrane round to reveal insulation if different material to ensure continuous seal. Fix vertical counter battens, then horizontal cladding battens Fix vertical timber cladding 4. Fix timber trims (fascia, bargeboard), Refix rainwater goods, service pipe work, reinstall new cills with thermal break below /inside and seal all round. 5. Apply antifungicide/UV protection stain to timber cladding.

Information about the performance values needed in the assessment Layers (near from exterior)

Thickness [m]

Properties Bulk Thermal conductivity density [kg/ m³] [W/mK]

Porosity [m³/m³]

Spec. heat capacity [J/(kgK)]

Timber board

0.025

0.23

455

0.73

1500

Air layer Breather membrane

0.025 0.001

0.28 2.3

1.3 130

0.001 0.001

1000 2300

Water vapour diffusion resistance 4.3

0.32 200

SUSREF Sustainable Refurbishment of Building Facades and External Walls Sheep’s wool quilt insulation Cement sand render Granite Lime mortar Granite Lime mortar Granite Interior gypsum plaster

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0.1

0.039

23

0.73

1800

9

0.025

1.2

2000

0.3

850

25

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.18 0.015

1.66 0.2

2453 850

0.095 0.65

702 850

54 8.3

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone) Approximate service life is 30 years: vapour-permeable membrane guarantee Timber will require re-application of UV & antifungal treatment, every 5 years. Betws y Coed weather data Criterion

Description

Thermal performance

Tranmission coefficient

Values

Unit W/(m2K)


Indoor climate


kg/m2/year

Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Conclusion

h/year

Lowest indoor surface temperature Conclusion

Overall conclusion Actions U-values U= 1.5 W/m2K – existing construction

h/year h/year

C


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U = 0.28 W/m2K with 100mm natural sheep wool

Impact on demand for heating HDD per year Nantlle Valley – 2260 with base load 15.5 C U = 1.5 x 2260/1000 x 24 kwh/m2 of wall per year = 65.088 kwh/m2 per year U = 0.28 x 2260/1000 x 24 kwh/m2 of wall per year = 15.187 kwh/m2 per year

Impact on energy demand for cooling Will reduce coldstore effect of wall beneficially

Impact on renewable energy use potential (using solar panels etc.) It would be possible to install PV panels on top of the timber cladding but weight would need to be considered.

Impact on daylight Reduction of solar radiation hitting stone wall. Possible reduction in daylight/sunlight if insulation of reveals reduces glazed areas.

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, Refurbishment concepts considers all materials (sheep wool, timber board and battens, wind screen, lamb wool, timber studs) and also impact from heating. Locally produced sheep wool is a waste product because that no lamb breeding impacts allocated to the wool and environmental impact for the wool is 0. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 1.5 W/m2 K, U-value for the concept with 100 mm natural sheep wool and ventilated timber cladding is 0.28 W/m2 K For heat flux and energy calculations heating degree days (HDD) based on +18oC. For London case it was 2868. Additional calculations are made for Nantlle Valley, were HDD based on +15oC and it was 2260. For impact calculations it is assumed that main heating energy type is gas. Impact parameters for gas (acquisition and use) are presented in the table below.


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Table. Environmental impact for heating type per 1 kWh used.

Heating energy type

kg CO2 eq/kWh 0.271

Gas

Non-renewable energy consumption, MJ/kWh 3.98

Non-renewable raw-material consumption, kg/kWh 0.088

600


CF heating 500 CF, material

400 300 200 100 0 Exist., London

Ref. (sheep wool+timber), London

Exist., Nantlle Valley

Ref. (sheep wool + timber), Nantlle Valley

Figure. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating, renovated wall considers carbon footprint from used materials and heating, but material impact is so small and therefore not visible in the figure. Heating type for both cases is gas.


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9 000 from heating

8 000

from material


7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist., London




Figure. Fossil energy consumption for existing-and refurbished walls. Existing wall considers only fossil energy from heating, renovated wall considers fossil energy from used materials and heating, but material impact is so small and therefore not visible the in figure. Heating type for both cases is gas.

200 from heating


180

from material

160 140 120 100 80 60 40 20 0 Exist., London




Figure 1. Non-renewable raw material consumption for existing-and refurbished walls. Existing wall considers only materials from heating use. Renovated wall considers renovation materials and materials used for heating, but material impact used in renovation is so small and therefore not visible in the figure. Heating type for both cases is gas.


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Environmental impact for used materials and for all three parameters (carbon footprint, fossil energy and nonrenewable raw material) is very small compared to the other SGG refurbishment cases (EPS or mineral wool) Main impact comes from heating.

Indoor air quality and acoustics Indoor air quality will be improved due to reduced condensation on walls. Better seals will increase sound proofness (wall mass already very soundproof).

Structural stability Negligeable effect.

Fire safety Natural sheep’s wool is inherently reluctant to burn. 90 mins fire resistance is required within 1m of a boundary line so an alterative non-combustible cladding would need to be substituted.

Aesthetic Quality Altered completely.

Effect on Cultural Heritage Only suitable for buildings where the external appearance is not of historic importance.

Life cycle costs Result for life cycle cost is showed in Table and Figure below. Results are calculated for the case London and Nantlle Valley. Same baseload values for HDD and energy calculation is used as presented in environmental impact calculations. Table. LCC calculation for the refurbishment case SGG1 and London.

Name: SGG1 Case London Concept: Internal insulation vapour-open of solid rubble stone wall with limesand pointing outside Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Natural sheeps wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Basic London 103

Renovated 100 mm 19

€/m2

€/m2

95 0 129 224

95 30 24 149


176 (232)

Figure 2. LCC for refurbishment case SGG1 and London. Table 1. LCC calculation for the refurbishment case SGG1 and Nantlle Valley.

Case: Nantlle Name: SGG1 Valley Concept: Internal insulation vapour-open of solid rubble stone wall with lime-sand pointing outside Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a

Natural sheeps wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Basic Nantlle Valley 81

Renovated 100 mm 15

€/m2

€/m2

95 0 101 196

95 30 19 144


177 (232)

Figure 3. LCC for the refurbishment case SGG1 and Nantlle Valley.

Need for care and maintenance Cladding timber should be treated with antifungicide and restained every 3-10 years (depends on orientation and whether close to trees)

Disturbance to the tenants and to the site Temporary interruption of services. Noise and disturbance is kept to outside but will last for several days/weeks dependent on size of building. Scaffolding with screening required for buildings of 2 storeys and above

Buildability Eminently buildable with ordinary construction skills but requires forethought and close supervision of details to avoid cold bridges and air infiltration


178 (232)

14 Concept number 2 by SGG – SGG 2: External insulation of solid rubble stone wall with semi-vapour-open mineral wool insulation material and acrylic render The method of external insulation of solid rubble stone wall with semi-vapour-open mineral wool insulation material and acrylic render insulating removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. System suppliers prefer to use authorised installers who have undergone training; and even so, installation requires forethought and close supervision of details to avoid cold bridges and air infiltration. The external appearance of pointed masonry is completely altered; but the external appearance of a rendered building may be accurately reproduced, including roughcast, smooth render bands and other decorative. The heating costs drop to about one tenth, and the life cycle costs over a period of 20 years drop to about half after the refurbishment.


Building Types – single and multi-storey buildings Current structure of external wall – Solid thick wall (400 – 1000 mm) built with two faces of stonework. No insulation. Climate zone - Zone 2 (Cfbw - mild, wet, windy)


Reasoning These thick walls (400mm – 1000mm) are built up with two faces of stonework with loose rubble packed between them to hold the external stone faces vertical. Some walls also have limited amounts of earth or mortar fill. The inner face was plastered. The outer face may be rendered or pointed. Significant air voids of irregular shape occur in the wall and through-stones are distributed all over wall, and around openings. These mean that cold bridges and actual air currents occur. Rain driven between stones can fall in the voids and land on a through-stone, emerging inside or outside. The method of insulating removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. The work can be carried out from outside without disturbing occupants. The materials used have a moderate carbon and resource-use footprint and can be partially recovered for recycling at the end of their life.


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Known problems relating to refurbishment method The overall build-up is thick (125mm), which may necessitate roof eaves and verges to be extended. Cills must be removed and replaced with deeper cills with a thermal break. Service entries (gas, air supply or extract, balanced flues, drainage pipework etc) need to be disconnected and adapted or relocated. Reveals to doors and windows cannot be insulated with the same method unless it is acceptable that the opening is much reduced in size. In gable wall with chimney, the insulation is not carried up around the chimney. The mineral wool insulation cannot continue down to ground level as it would be adversely affected by water so the lowest part of the wall must be insulated using a different non-capillary material(rendered or The external appearance of pointed masonry is completely altered. The external appearance of a rendered building may be accurately reproduced, including roughcast, smooth render bands and other decorative features.



600 mm rubble walling with cement/sand pointing 20 mm internal cement/sand basecoat and gypsum plaster

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Cross section of the refurbishment concept

181 (232)


182 (232)

Summary of the materials and layers thickness 1. Acrylic render system 12-15mm with fibre mesh embedded 2. 110mm mineral wool slab mechanically fixed to existing wall 3. 25mm pebbledashed cement/sand render (existing wall) 4. 600mm solid stone rubble wall (existing Wall) 5. 15mm internal plaster of cement:sand + gypsum skim (existing wall)

Description of working method 1. Check condition and verticality of existing wall Check projection of roof at eaves & verges Check margin available at reveals for insulation Note cills and other abutment/attachment/projections forming cold bridges Decide strategy on chimneys (remove redundant chimneys and close roof? Stop insulation at base of chimney and provide cover flashing to insulation?) Check ground levels and possibility of installing land drain 2. Strip eaves & verges and extend, reslate Remove cills & hack off render from existing reveals; fix new cill brackets Remove rainwater goods, alter service pipework etc. Excavate trench and lay land drains 3. Fix base insulation XPS and render with self-coloured acrylic system (requires stainless steel lath) Fix wall insulation and render with acrylic render system, including mesh. Carry system round to reveal insulation (phenolic foam for reduced thickness) and seal all round all perforations, opening and junctions 4. Fix timber trims (fascia, bargeboard), Refix rainwater goods, service pipe work, reinstall new cills with thermal break below /inside and seal all round.

Sealing of window and door frames and other openings Doors and windows are being replaced. (see SGG type 3 for retaining existing windows) Install new doors and windows at outer face of existing wall so that insulation can be sealed to door or window frame. As part of making good internally where old doors or windows were removed, hack off old plaster and line internal reveals with phenolic foam/plasteboard laminate. Service entries must be sealed.


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Information about the performance values needed in the assessment Materials (from exterior to interior) Acrylic stucco Mineral wool (mechanical fix) Cement sand render Granite Lime mortar Granite Lime mortar

Thickness [m]


Porosity [m³/m³]



0.02

0.371

1795

0.275

840

0.1

0.04

60

0.95

850

1.3

0.025

1.2

2000

0.3

850

25

0.185 0.025 0.185 0.025

1.66 0.7 1.66 0.7

2453 1785 2453 1785

0.095 0.28 0.095 0.28

702 850 702 850

54 15 54 15

Durability (with reference to required service life) and hygrothermal behaviour (in applied climatic zone)

Service life of up 60 years claimed by system supplier. Betws y Coed weather data Criterion

Description

Values

Unit

Thermal performance


17

W/(m2K)


8

W/(m2K)

103

h/year

Moisture performance of

External surface Risk for frost damage

SUSREF Sustainable Refurbishment of Building Facades and External Walls existing construction (south orientation)

Moisture performance of refurbished construction ( south orientation)

T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential

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8657

h/year

8657

h/year

0.02

Kg/year

311

h/year

8449

h/year

8449

h/year

0

Kg/year

Indoor climate after refurbishment


Overall conclusion

The concept is performing a little better after refurbishment in terms of its drying potential and, mould growth and condensation on the exterior surface of the wall. However, the risk of frost damage increases with the refurbishment. Even after refurbishment the TOW values are much higher which might increases the risk for mould growth and corrosion on the external surface and also behind the acrylic plaster. The risk is higher for the south west orientation with heavy driving rain compared to the south orientation.

Actions

The risk of biological growth and condensation on the exterior surface must be kept in mind when choosing the surface finishing materials and paints.

19.2

C


Impact on energy demand for cooling Will reduce cold store effect of wall beneficially

Impact on renewable energy use potential (using solar panels etc) It would be possible to install PV panels on top of the render system but only if fixing pattresses or brackets fixed to masonry with resin anchors were inserted into the wall insulation forming local cold bridges.



185 (232)

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, Refurbishment concepts considers refurbishment materials (mineral wool, 3-layer cement-lime render, metal mesh) and impact from heating. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 1.5 W/m2 K, U-value for the concept with 110 mm rock wool and render is 0.29 W/m2 K For heat flux and energy calculations heating degree days (HDD) based on +18oC. For London case it was 2868. Additional calculations are made for Nantlle Valley, were HDD based on +15oC and it was 2260. For impact calculations it is assumed that main heating energy type is gas. Impact parameters for gas acquisition and use are presented in the table below. Table 2. Environmental impact for heating type per 1 kWh used. Heating energy type

kg CO2 eq/kWh 0.271

gas



600

CF heating


500

CF, material

400 300 200 100 0 Exist., London

Ref. (min.wool+render), London


Ref.(min wool + render), Nantlle Valley


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Figure 4. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating, renovated wall considers carbon footprint from used materials and heating, but material impact is so small and therefore not visible in the figure. Heating type for both cases is gas. 9 000 from heating

8 000

from material


7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist., London

Ref. (min.wool+render), London


Ref.(min wool + render), Nantlle Valley

Figure 5. Fossil energy consumption for existing-and refurbished walls. Existing wall considers only fossil energy from heating, renovated wall considers fossil energy from used materials and heating, but material impact is so small and therefore not visible in the figure. Heating type for both cases is gas.

200 from heating


180

from material

160 140 120 100 80 60 40 20 0 Exist., London

Ref. (min.wool+render), Exist., Ref.(min wool + render), London Nantlle Valley Nantlle Valley

Figure 6. Non renewable raw material consumption for existing-and refurbished walls. Existing wall considers only materials from heating use. Renovated wall considers renovation materials and materials used for heating. Heating type for both cases is gas.


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Materials used in this refurbishment concept (mineral wool + render) have a little lower environmental impact than in the concepts with EPS + render.


Structural stability Negligible effect.

Fire safety Mineral wool does not support combustion.

Aesthetic Quality Possible to reproduce features moulded into render. If the building previously had wide roof overhangs at roof eaves and verge, these will be reduced/lost.



188 (232)

Life Cycle Costs Result for life cycle cost is showed in Table and Figure below. Results are calculated for the case London and Nantlle Valley. Same base load values for HDD and energy calculation is used as presented in environmental impact calculations. Table 3. LCC calculation for the refurbishment case SGG2 and London.

Name: SGG2 Case London Concept: Internal insulation vapour-open of solid rubble stone wall with lime-sand pointing outside Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Figure 7. LCC for the refurbishment case SGG2 and London.

Basic London 103

110 mm 20

€/m2

€/m2

95 0 129 224

95 20 25 140


189 (232)

Table 4. LCC calculation for the refurbishment case SGG2 and Nantlle Valley.

case: Nantlle Name: SGG2 Valley Concept: Internal insulation vapor-open of solid rubble stone wall with lime-sand pointing outside Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a

Mineral wool Heating energy (kWh/m2/a)


110 mm 16

€/m2

€/m2

95 0 101 196

95 20 20 135



Need for care and maintenance Acrylic finish seems to harbour algae and may require washing down with a pressure hose and or algicide from time to time.

Disturbance to the tenants and to the site Temporary interruption of services. Noise and disturbance is mainly outside but as windows and doors are being replaced and internal reveals made good, tenant may prefer to move out temporarily. Scaffolding with screening required for buildings of 2 storeys and above .


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Buildability System suppliers stipulate use of authorised installers who have undergone training. Even so, installation requires forethought and close supervision of details to avoid cold bridges and air infiltration Uncoated mineral wool is unpleasant to handle but can be used with nylon mesh in a two-pass one coat finish. Coated mineral wool is less unpleasant to handle but must be used with stainless steel lath in a two-coat finish system. The stainless steel lath is hard to handle even with gloves and frequently injures operatives.


191 (232)

15 Concept number 3 by SGG – SGG 3: External insulation of solid rubble stone wall with expanded polystyrene insulation material and acrylic render External insulation of solid rubble stone wall with expanded polystyrene (EPS) insulation material and acrylic render removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. Also the condensation on walls reduces. The external appearance of pointed masonry is completely altered, but the external appearance of a rendered building may be accurately reproduced, including roughcast, smooth render bands and other decorative. System suppliers prefer to use authorised installers who have undergone training; even so, installation requires forethought and close supervision of details to avoid cold bridges and air infiltration. The costs of heating drop significantly.




Reasoning These thick walls (400mm – 1000mm) are built up with two faces of stonework with loose rubble packed between them to hold the external stone faces vertical. Some walls also have limited amounts of earth or mortar fill. The inner face was plastered. The outer face may be rendered or pointed. Significant air voids of irregular shape occur in the wall and through-stones are distributed all over wall, and around openings. These mean that cold bridges and actual air currents occur. Rain driven between stones can fall in the voids and land on a through-stone, emerging inside or outside. The method of insulating removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. The work can be carried out from outside without disturbing occupants. The materials used have a moderate carbon and resource-use footprint and can be partially recovered for recycling at the end of their life.

Known problems relating to refurbishment method The overall build-up is thick (125mm), which may necessitate roof eaves and verges to be extended. Cills must be removed and replaced with deeper cills with a thermal break.


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Service entries (gas, air supply or extract, balanced flues, drainage pipework etc) need to be disconnected and adapted or relocated. Reveals to doors and windows cannot be insulated with the same method unless it is acceptable that the opening is much reduced in size. (If roof, doors and windows are to be replaced at the same time as the external walls are clad, these can be extended/relocated to suit the insulation at very little additional cost and without significant reduction in opening size.) In gable wall with chimney, the insulation is not carried up around the chimney. The mineral wool insulation cannot continue down to ground level as it would be adversely affected by water so the lowest part of the wall must be insulated using a different non-capillary material(rendered or The external appearance of pointed masonry is completely altered. The external appearance of a rendered building may be accurately reproduced, including roughcast, smooth render bands and other decorative. SEALING OF WINDOW AND DOOR FRAMES AND OTHER OPENINGS

Existing windows and doors are retained (see SGG type 2 for replacing doors and windows). External reveal insulation (a thinner insulation material e.g. phenolic foam board) must be sealed to frames. Existing cills need replacing, with phenolic foam beneath them. Service entries must be sealed.



600 mm rubble walling with cement/sand pointing. 15 mm internal cement/sand basecoat and gypsum plaster.

193 (232)


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Cross section of the refurbishment concept: 1.

Acrylic render system 12-15mm with fibre mesh embedded

2.

110mm expanded polystyrene slab mechanically fixed to existing wall

3.

25mm pebbledashed cement/sand render (existing wall)

4.

600mm solid stone rubble wall (existing wall)

5.

15mm internal plaster of cement:sand + gypsum skim (existing wall) Sealing of window and door frames and other openings


195 (232)


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Description of working method 1. Check condition and verticality of existing wall Check projection of roof at eaves & verges Check margin available at reveals for insulation Note cills and other abutment/attachment/projections forming cold bridges Decide strategy on chimneys (remove redundant chimneys and close roof? Stop insulation at base of chimney and provide cover flashing to insulation?) Check ground levels and possibility of installing land drain 2. Strip eaves & verges and extend, reslate Remove cills & hack off render from existing reveals; fix new cill brackets Remove rainwater goods, alter service pipework etc Excavate trench and lay land drains 3. Fix base insulation XPS and render with self-coloured acrylic system (requires stainless steel lath) Fix wall insulation and render with acrylic render system, including mesh. Carry system round to reveal insulation (phenolic foam for reduced thickness) and seal all round all perforations, opening and junctions 4. Fix timber trims (fascia, bargeboard), Refix rainwater goods, service pipe work, reinstall new cills with thermal break below /inside and seal all round.

Information about the performance values needed in the assessment Materials (from exterior to interior)

Acrylic stucco EPS (mechanical fix) Cement sand render Granite Lime mortar Granite Lime mortar

Thickness [m]


Porosity [m³/m³]



0.02

0.371

1795

0.275

840

0.1

0.04

30

0.95

1500

50

0.025

1.2

2000

0.3

850

25

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15


197 (232)

Durability (with reference to required service life)

Approximate service life is 60 years. Betws y Coed weather data Criterion

Description

Values

Unit

Thermal performance


17

W/(m2K)


8

W/(m2K)

103

h/year

8657

h/year

8657

h/year

0.02

Kg/year

316

h/year

8444

h/year

8444

h/year

-0.05

Kg/year

Moisture performance of existing construction (south orientation)

Moisture performance of refurbished construction (south orientation)

External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential



Overall conclusion

The concept performs well after refurbishment in terms of its drying potential; however the risk for frost damage is increased with little decrease in mould growth

19.1

C


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and condensation on the exterior surface of the wall. However, even after refurbishment the TOW values are higher which increases the risk for mould growth and condensation on the external surface and also behind the plaster. The risk will be higher for the south west orientation with heavy driving rain compared to the south orientation.

Actions

The risk of biological growth and frost damage on the exterior surface must be kept in mind when choosing the colour of the paint.

U= 1.5 W/m2K – existing construction U = 0.29 W/m2K with 110mm EPS


Impact on energy demand for cooling Will reduce cold store effect of wall beneficially

Impact on renewable energy use potential (using solar panels etc.) It would be possible to install PV panels on top of the render system but only if fixing pattresses or brackets fixed to masonry with resin anchors were inserted into the wall insulation forming local cold bridges


Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, Refurbishment concepts considers all refurbishment materials (EPS , render with metal mesh) and impact from heating. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 1.5 W/m2K, U-value for the concept with 110 mm EPS and 15 mm render is 0.29 W/m2K For heat flux and energy calculations heating degree days (HDD) based on +18oC. For London case it was 2868.


199 (232)

Additional calculations are made for Nantlle Valley, were HDD based on +15oC and it was 2260. For impact calculations it is assumed that main heating energy type is gas. Impact parameters for gas acquisition and use are presented in the table below. For impact of heating energy main heating type is used. These presented in table below. Table 5. Environmental impact for heating type per 1 kWh used. Heating energy type gas

kg CO2 eq/kWh 0.271




600

CF heating

500

CF, material

400 300 200 100 0 Exist., London

Ref. (EPS+render), London

Exist.,Nantlle Valley

Ref.(EPS + render), Nantlle Valley

Figure 1. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating, renovated wall considers carbon footprint from used materials and heating. Heating type for both cases is gas..


200 (232)

9 000

from heating

8 000 from material


7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist., London

Ref. (EPS+render), London

Exist.,Nantlle Valley

Ref.(EPS + render), Nantlle Valley

Figure 2. Fossil energy consumption for existing-and refurbished walls. Existing wall considers only fossil energy from heating, renovated wall considers fossil energy from used materials and heating. Heating type for both cases is gas.


201 (232)


200

from heating

180

from material

160 140 120 100 80 60 40 20 0 Existing solid wall

Ren. 110 mm EPS + render

Existing solid wall

Ren. 110 mm EPS + render

Figure 3. Non renewable raw material consumption for existing-and refurbished walls. Existing wall considers only materials from heating use. Renovated wall considers renovation materials and materials used for heating. Heating type for both cases is gas. EPS + render have a higher carbon footprint compared to other renovation concepts (sheep wool or mineral wool). Main environmental impact, carbon footprint, comes from space heating.


Structural stability Negligible effect.

Fire safety EPS does not burn readily but shrinks from flame. It cannot be used close to boundaries. Mineral wool firebreaks must be incorporated at fire-compartment part walls or floors, and around hot service penetrations.

Aesthetic Quality Possible to reproduce features moulded into render. Necessary to extend roof or to alter angle of roof at eaves which may produce an unfamiliar appearance.

Effect on Cultural Heritage Only suitable for buildings where the external appearance is not of historic importance


202 (232)


Name: SGG3 Case: London Concept: External insulation of solid rubble stone wall with expanded polystyrene insulation material and acrylic render Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a EPS Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Figure 9. LCC for refurbishment case SGG3 and London.

Basic London

110 mm 103 €/m2

95 0 129 224


203 (232)

Table 7. LCC calculation for the refurbishment case SGG3 and Nantlle Valley.

Name: SGG3 Nantlle Valley Concept: External insulation of solid rubble stone wall with expanded polystyrene insulation material and acrylic render Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a

EPS Heating energy (kWh/m2/a)


100 mm 16

€/m2

€/m2

95 0 101 196

95 20 20 135


Figure 10. LCC for refurbishment case SGG3 and Nantlle Valley.

Need for care and maintenance Acrylic finish seems to harbour algae and may require washing down with a pressure hose and or algicide from time to time.

Disturbance to the tenants and to the site Temporary interruption of services. Noise and disturbance is kept to outside but will last for several days/weeks dependent on size of building. Scaffolding with screening required for buildings of 2 storeys and above


204 (232)

Buildability System suppliers prefer to use authorised installers who have undergone training. Even so, installation requires forethought and close supervision of details to avoid cold bridges and air infiltration EPS is easy to handle.


205 (232)

16 Concept number 4 by SGG – SGG 4: External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding The refurbishment concept of External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding removes wind and rain from the external face of the stonework. It reduces air movement across the face of the wall and into gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm. It will benefit from solar gain that can reach the massive stone wall through the relatively still air in the cavity. After the refurbishment there will never be need for cooling. This concept is only suitable for buildings where the external appearance is not of historic importance.




Reasoning These thick walls (400mm – 1000mm) are built up with two faces of stonework with loose rubble packed between them to hold the external stone faces vertical. Some walls also have limited amounts of earth or mortar fill. The inner face was plastered. The outer face may be rendered or pointed. Significant air voids of irregular shape occur in the wall and through-stones are distributed all over wall, and around openings. These mean that cold bridges and actual air currents occur. Rain driven between stones can fall in the voids and land on a through-stone, emerging inside or outside. The method of sheltering the wall removes wind and rain from the external face of the stonework. It reduces air movement across the face of the wall and into gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm. It will benefit from solar gain that can reach the massive stone wall through the relatively still air in the cavity. The work can be carried out from outside without disturbing occupants. The materials used have a moderate carbon and resource-use footprint and can be fully recovered for recycling, composting or combustion at the end of their life.

Known problems relating to refurbishment method The minimum build up is 25mm - 50mm air gap plus the sheet profile depth, but may be considerably greater if the wall is not vertical or has stones projecting from it, which may necessitate roof eaves and verges to be extended. Cills may need to be removed and replaced with deeper cills with a thermal


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break. (If roof, doors and windows are to be replaced at the same time as the external walls are sheltered, these can be extended/relocated to suit the shelter-cladding at little additional cost.) Service entries (gas, air supply or extract, balanced flues, drainage pipework etc) need to be disconnected and adapted or relocated. In gable wall with chimney, the screening insulation is not carried up around the chimney Reveals to doors and windows need to be lined with flat steel sheet to ensure continuity of shelter and seal. The steel sheet cladding can be continued down to ground level if the internal floor level is close to external ground level but should be formed of a separate sheet as its life will be shorter than that on the main part of the wall The external appearance of pointed or rendered masonry is completely altered.

Sealing of window and door frames and other openings If existing windows and doors are retained, external reveals may be lined with flat steel sheetin a light colour, sealed all round. Service entries must be sealed.

VENTILATION & HEATGAIN Simple sealed shelter may benefit from passive heatgain. A development of this principle would be to use the SolarWall. This is a registered trademark system of micro-perforated steel sheet sealed to the wall, with a thermostatically controlled fan to move warm air into the building when internal air temperatures are below those within the SolarWall and within comfort range. Alternatively, a SolarWall could be combined with an air-sourced heat pump.



1000 mm rubble stonework with cement/sand pointing 15mm cement/sand + gypsum skim internal plaster

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Cross section of the refurbishment concept 1. Acrylic or powder-coated galvanised profiled steel sheet fixed at av 300mm horizontal centres to galvanised rails at average 850mm vertical centres fixed to 2. Steel Z-fixings 850mm vertical centres fixed to 50 x 100 vertical timber studs at 2000mm centre 3. 1000mm solid stone rubble wall, heavily cement pointed 4. 15mm internal plaster (cement:sand + gypsum skim)

Steel sheet is to be sealed at all edges to achieve designed air-tightness of 1 air change per hour.


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Description of working method 1. Check condition and verticality of existing wall Check projection of roof at eaves & verges Check margin available at reveals for lining Note cills and other abutment/attachment/projections dictating cavity size Decide strategy on chimneys (remove redundant chimneys and close roof? Stop shelter cladding at base of chimney and provide cover flashing?) Check ground levels and internal (consider installing land drain) 2. If necessary: (not required at test house) strip eaves & verges and extend, reslate Remove rainwater goods, alter service pipework etc Excavate trench and lay land drains 3. Fix proprietary steel stools to masonry at maximum 1500mm horizontal centres, packing out as necessary. 4. Fix horizontal cladding rails at maximum 1800 mm vertical centres 5. Form 100mm wide vertical render bands at corners (if shelter does not extend round corner to another elevation,) to take up irregularity in stonework so that steel sheet can be sealed at all edges. 6. Form render band across bottom of sheeting (bottom edge of band to be approx 200mm above ground level, ready for sealing 7. Install sheeting using proprietary external grade double sided sealing tap at all laps and at render bands. Seal round reveals, at window and eaves/verge soffit and at bottom of main wall shelter 8. Fix timber trims (fascia, bargeboard), refix rainwater goods, service pipe work, install new cover cills and reveal cladding with thermal break if space allows, and seal all round.


Thickness [m]

Sheltered opaque

Corrugated steel sheet Air layer

Cement sand render Granite Lime mortar Granite Lime mortar Granite Interior gypsum plaster


Porosity [m³/m³]


Water vapour diffusion resistance 450

0.01

50

7800

0.0001

0.28

1.3

0.001

1000

0.025

0.075 average 1.2

2000

0.3

850

25

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.18 0.015

1.66 0.2

2453 850

0.095 0.65

702 850

54 8.3


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Durability (with reference to required service life) and hygrothermal behaviour (in applied climate zone)

Maximum service life is 40 years Betws y Coed weather data Criterion

Description

Values

Unit

Thermal performance


17

W/(m2K)


8

W/(m2K)

103

h/year

8657

h/year

8657

h/year

0.04

Kg/year

0

h/year

3087

h/year

114

h/year

8646

h/year

8305

h/year

Moisture performance of existing construction (south orientation)

Moisture performance of refurbished construction ( south orientation)

External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Risk for mould, corrosion behind corrugated sheet T>0 C, RH>80% Risk for mould, corrosion behind air gap T>0 C, RH>80%


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Drying potential

-0.020

Kg/year



16.7

Overall conclusion

The concept performs better after refurbishment in terms of its drying potential and the risk for frost damage, mould growth and condensation on the exterior surface of the wall. However the mould growth risk behind the corrugated sheet and behind air gap is higher after refurbishment. The risk is higher for the south west orientation with heavy driving rain compared to the south orientation.

Actions

The risk of biological growth behind the shelter must be kept in mind when selecting the ventilation rate. Increase in air change per hour might reduce the risk of mould growth.

C

U-values U= 1.5 W/m2K – existing construction U = 1.18 W/m2L with av. 75mm airspace, 1 air change per hour

Impact on demand for heating The shelter will reduce the wetness of the wall and the wind-chill effect, and reduce night-cooling. HDD per year Nantlle Valley – 2260 with base load 15.5 C U = 1.5 x 2260/1000 x 24 kwh/m2 of wall per year = 81.36 kwh/m2 per year U = 1.18 x 2260/1000 x 24 kwh/m2 of wall per year = 64.003 kwh/m2 per year

Impact on energy demand for cooling Never any demand for cooling!

Impact on renewable energy use potential (using solar panels etc) It would be possible to install PV panels on top of the shelter system but only if fixing pattresses or brackets back to the masonry with resin anchors . It would be beneficial to use the preheated air in conjunction with an air-sourced heat pump displacing the oilfired heating system.Impact on daylight

Impact on daylight None.

Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption LCA is made according to next assumptions:


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Life span is 20 year, A refurbishment concept considers refurbishment materials (galvanized profiled steel sheet, vertical timber studs) and impact from heating. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 1.5 W/m2K, U-value for the concept where solid stone wall covered with steel sheet is 1.18 W/m2K For heat flux and energy calculations heating degree days (HDD) based on +18oC. For London case it was 2868. Additional calculations are made for Nantlle Valley, were HDD based on +15oC and it was 2260. For impact calculations it is assumed that main heating energy type is gas. Impact parameters for gas acquisition and use are presented in the table below. Table 8. Environmental impact for heating type per 1 kWh used. Heating energy type gas

kg CO2 eq/kWh 0.271




600

CF heating

500

CF, material

400 300 200 100 0 Exist., London

Ref. (steel sheet), London

Exist.,Nantlle Ref.(steel sheet), Valley Nantlle Valley

Figure 1. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating, renovated wall considers carbon footprint from used materials and heating. Heating type for both cases is gas.

SUSREF


Sustainable Refurbishment of Building Facades and External Walls

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9 000

from heating

8 000

from material

7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist., London


Exist., Ref.(steel sheet), Nantlle Valley Nantlle Valley

Figure 2. Fossil energy consumption for existing-and refurbished walls. Existing wall considers only fossil energy from heating, renovated wall considers fossil energy from used materials and heating. Heating type for both cases is gas. from heating

200

from material


180 160 140 120 100 80 60 40 20 0 Exist., London



Ref.(steel sheet), Nantlle Valley

Figure 3. Non-renewable raw material consumption for existing-and refurbished walls. Existing wall considers only materials from heating use. Renovated wall considers renovation materials and materials used for heating. Heating type for both cases is gas.

Renovation materials have small carbon footprint compared to the heating needed..


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Indoor air quality and acoustics Indoor air quality will be improved due to reduced condensation on walls. It is unknown whether cladding will attenuate or amplify the wind that comes up the valley and hits the gable.

Structural stability Negligeable effect.

Fire safety No issues.

Aesthetic Quality Loss of pointed stonework. If the building previously had wide roof overhangs at roof eaves and verge, these will be reduced/lost. Test building is located just within the National park, so has required planning permission.


Life Cycle Costs Result for life cycle cost is showed in Table and Figure below. Results are calculated for the case London and Nantlle Valley. Same baseload values for HDD and energy calculation is used as presented in environmental impact calculations. Table 9. LCC calculation for the refurbishment case SGG4 and London.

Name: SGG4

London

Concept: External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plasterin25mm calcium silicate board g with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Basic London 103

Refurbished 81

€/m2

€/m2

90 0 129 219

90 40 101 231


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Table 10. LCC calculation for the refurbishment case SGG4 and Nantlle Valley. Nantlle Name: SGG4 Valley Concept: External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a

Heat plasterin25mm calcium silicate board g with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost


Refurbished 64

€/m2

€/m2

90 0 101 191

90 40 80 210


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Need for care and maintenance Occasional wash to remove algae. Repaint every ten years.

Disturbance to the tenants and to the site Temporary interruption of services. Noise and disturbance is kept to outside but will last for several days/weeks dependent on size of building. Scaffolding with screening required for buildings of 2 storeys and above.

Buildability Simple technology: likely to be a low cost – low efficacy upgrade, suitable for DIY or small nonspecialist contractors. (SolarWall will require an electrician to connect the fan and controls)


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17 Concept number 5 by SGG – SGG 5: Internal insulation vapouropen of solid rubble stone wall with lime-sand pointing outside The concept of internal insulation vapour-open of solid rubble stone wall with lime-sand pointing outside is only suitable for buildings where the internal wall finish/details are not of historic importance. The concept may be favourable where external conservation is essential, but there is a damage risk as the outer face of masonry wall will be colder and may suffer from increased staining or frost damage as a result. This concept is designed to absorb fluctuations of humidity and release the excess when the peak of humidity has passed. Indoor air quality will be improved due to reduced condensation on walls. The construction technology is simple with normal trade skills. The system is imported, and expensive compared to more available mass market vapour-closed alternatives. If using thicker insulation board, cold bridging would need greater consideration and careful detailing.




Reasoning These thick walls (400mm – 1000mm) are built up with two faces of stonework with loose rubble packed between them to hold the external stone faces vertical. Some walls also have limited amounts of earth or mortar fill. The inner face was plastered. The outer face may be rendered or pointed. Significant air voids of irregular shape occur in the wall and through-stones are distributed all over wall, and around openings. These mean that cold bridges and actual air currents occur. Rain driven between stones can fall in the voids and land on a through-stone, emerging inside or outside. When the external appearance of a pointed masonry wall must be retained for aesthetic and/or historical reasons, insulation must be installed internally. A vapour-open system is usually recommended because an internal vapour barrier is very hard to install correctly in an existing structure. With a vapour barrier there is a high risk of trapping moisture within the masonry, causing corrosion or rot in any embedded steel or timber beams, floor joists, lintels, wall plates etc. This system is designed to absorb fluctuations of humidity and release the excess when the peak of humidity has passed. The work can be carried out when internal surfaces are degraded or of limited aesthetic/historic importance.

Known problems relating to refurbishment method Disruption to occupants


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Trims (skirtings, architraves, cornices, inner cills etc) may need to be replaced or extended Services may need to be altered (depending on thickness of insulation used). The minimum thickness of the system is 35mm (6mm adhesive 25mm board 4mm finish) which may be accommodated in most rooms but gives little energy improvement. Cold bridging occurs at structural lines (walls, ground and intermediate floors) and may be a reason to limit the thickness of insulation to be installed. Outer face of masonry wall will be colder and may suffer from increased staining or frost damage as a result.

Sealing of window and door frames and other openings If historic windows/doors remain, it is preferred to rely on traditional lime plaster wet finish to provide a seal and not to use modern mastics and adhesives If windows/doors are being replaced in timber, system includes a compressed tape for use around the frame behind the wet finish to take up any timber shrinkage Service entries should be sealed with compressed foam or mastic, and plastered PART-PLAN OF THE EXISTING WALL

SUSREF Sustainable Refurbishment of Building Facades and External Walls PART-PLAN OF THE REFURBISHMENT CONCEPT

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Cross section of the refurbishment concept

Cross section of the refurbishment concept 1. 600mm solid stone rubble wall, pointed with lime/sand mortar 2. Average 10mm hair/lime/sand basecoat plaster to close face of wall and bring to flush 3. 6mm special adhesive with limited vapour permeability 4. 25mm (or 30mm) Calcium Silicate board 5. 4mm special thin-coat plaster applied in 2 coats


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Description of working method 1. Check: if condition of existing internal wall finish will allow direct application of adhesive; limitations on thickness of insulation to be installed due to fixtures and fittings, room dimensions, or services margin available at reveals for lining 2. Remove skirtings, architraves, electrical power and lighting covers 3. Remove and replace existing wall plaster if hollow, friable or otherwise degraded 4. Apply adhesive and fix calcium silicate board 5. Install tape at cracks and joints, edge sealing tapes 6. Apply finish coats to calcium silicate board 7. Refix skirtings and other trims

Sealing of window and door frames and other openings If historic windows/doors remain, it is preferred to rely on traditional lime plaster wet finish to provide a seal and not to use modern mastics and adhesives If windows/doors are being replaced in timber, system includes a compressed tape for use around the frame behind the wet finish to take up any timber shrinkage Service entries should be sealed with compressed foam or mastic, and plastered


Granite Lime mortar Granite Lime mortar Granite Interior Lime plaster KP adhesive Calsitherm Lime plaster

Thickness [m]


Porosity [m³/m³]


Water vapour diffusion resistance 54 15

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

0.185 0.025

1.66 0.7

2453 1785

0.095 0.28

702 850

54 15

0.18 0.015

1.66 0.7

2453 1600

0.095 0.3

702 850

54 7

0.006

0.93

1410

0.468

1059

35

0.05 0.004

0.057 0.71

222 1600

0.92 0.3

1303 850

5.4 7


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Durability (with reference to required service life) and hygrothermal behaviour in applied climatic zone)

Approximate service life is 60 years Betws y Coed weather data Criterion

Description

Values

Unit

Thermal performance


17

W/(m2K)


8

W/(m2K)

0

h/year

3355

h/year

343

h/year

-0.59

Kg/year

5

h/year

4500

h/year

902

h/year

0.63

Kg/year

Moisture performance of existing construction (north-west orientation)

Moisture performance of refurbished construction (north-west orientation)

External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential External surface Risk for frost damage T95% Risk for mould, corrosion T>0 C, RH>80% Risk for condensation, algae, decay T>0 C, RH>95% Drying potential


Lowest indoor surface temperature 18

Overall

The concept does not perform better after refurbishment in terms of its drying

C


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conclusion

potential and also the risk for frost damage increases, with mould growth and condensation on the exterior surface of the wall. However, even after refurbishment the TOW values are much higher which increases the risk for mould growth and condensation on the external surface and also behind the interior lime plaster. The risk will be higher for the south west orientation with heavy driving rain compared to the north west orientation.

Actions

The risk of biological growth and frost damage on the exterior surface and also behind the existing interior plaster must be kept in mind when choosing the internal insulation and its thickness for refurbishment.

U= 1.7 W/m2K – existing construction U = 0.68 W/m2K with 50mm calcium silicate board (NB test wall will have only 25mm calcium silicate board thickness installed due to existing historic fittings)

Impact on demand for heating Will reduce condensation and mould on inner face of wall HDD per year Nantlle Valley – 2260 with base load 15.5 C U = 1.7 x 2260/1000 x 24 kwh/m2 of wall per year = 92.21 kwh/m2 per year U = 0.68 x 2260/1000 x 24 kwh/m2 of wall per year = 36.88 kwh/m2 per year

Impact on energy demand for cooling Never any demand for cooling!

Impact on renewable energy use potential (using solar panels etc) No impact


Environmental impact Environmental impact from the wall refurbishment concept depends on energy renovation level, building location, building materials used, and energy source used for heating. Impact parameters which considered were carbon footprint, fossil energy- and non-renewable raw material consumption. LCA is made according to next assumptions: Life span is 20 year, Life span is 20 year, Refurbishment concept considers refurbishment materials (internal calcium silicate board) and impact from heating. For existing wall no construction materials is considered only impact from heating is calculated. U-value for existing wall is 1.7 W/m2K,


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U-value for the internal insulation concept where solid stone wall covered with 50 mm calcium silicate board is 0.68 W/m2K For heat flux and energy calculations heating degree days (HDD) based on +18oC. For London case it was 2868. Additional calculations are made for Nantlle Valley, were HDD based on +15oC and it was 2260. For impact calculations it is assumed that main heating energy type is gas. Impact parameters for gas acquisition and use are presented in the table below. For impact of heating energy main heating type is used. These presented in table below. Table 11. Environmental impact for heating type per 1 kWh used. kg CO2 eq/kWh

Heating energy type

0.271

gas



700

CF heating


600 CF, material

500 400 300 200 100 0 Exist., London

Ref. (internal cal.silicate board) London


Ref.(Internal cal.silicate board) Nantlle Valley

Figure 1. Carbon footprint for existing-and refurbished walls. Existing wall considers only carbon footprint from heating, renovated walls considers carbon footprint from used materials and heating. Heating type for both cases is gas.


10 000

from heating

9 000 8 000


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from material

7 000 6 000 5 000 4 000 3 000 2 000 1 000 0 Exist., London

Ref. (internal Exist., Ref.(Internal cal.silicate board) Nantlle Valley cal.silicate board) London Nantlle Valley

Figure 2. Fossil energy consumption for existing-and refurbished walls. Existing wall considers only fossil energy from heating, renovated walls considers fossil energy from used materials and heating. Heating type for both cases is gas.

Materials have moderate carbon footprint and fossil energy consumption. Energy efficiency effects after renovation remain small and that for impact from heating is higher than impact from materials.

Indoor air quality and acoustics Indoor air quality will be improved due to reduced condensation on walls. Better seals at windows will increase sound proofness (wall mass already very soundproof).

Structural stability Negligible effect, because moisture is not trapped in walls.

Fire safety No issues – materials are inherently fire-resisting.

Aesthetic Quality Loss of part of depth/moulding of trims if thin insulation is installed on wall with thick skirting or cornice. These details can be removed and reinstalled, or reproduced, at additional cost.

Effect on Cultural Heritage Only suitable for buildings where the internal wall finish/details are not of historic importance so that they may not be moved


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Name: SGG5 London Concept: Internal insulation vapour-open of solid rubble stone wall with lime-sand pointing outside Calculation period: 20 years Cost level: 6/2011 Real change of energy price: + 2 %/a Heat plastering 25mm calcium silicate board + with mineral wool Heating energy (kWh/m2/a) ECONOMICAL EFFECTS Basic renovation cost Extra renovation cost Heating cost/20 y Life Cycle Cost

Basic London 117

25 mm 47

€/m2

€/m2

90 0 146 236

90 20 59 169


Need for care and maintenance Material is resistant to mould growth. Finish may be decorated with limewash or other vapour-open paints.


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Disturbance to the tenants and to the site Work from inside so no need for scaffolding. Rooms must be stripped bare. Temporary interruption of services.

Buildability Simple technology, normal trade skills but an imported system, expensive compared to more available mass market vapour-closed alternatives. If using thicker insulation board, cold bridging would need greater consideration and careful detailing


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18 Summarising remarks on the concepts Concept number 1 by VAHANEN – B1 Brick wall with ventilation gap and vacuum insulated panel is potentially useful for a large bulk of buildings (especially residential and educational) constructed mainly during the post-war era prior to industrial (concrete) elements emerged to these needs. The original external brick walls are solid with insulation (typically mineral wool); the refurbishment method replaces the old insulation by adding a vacuum insulated panel with an air cap. The markets are in the cold and dry climate, where the air cap id efficient for the building physics. The method is attractive, when the old brick surface is damaged and needs actions also for that reason. The concept has several good points, including ease of adopting the needed workmanship skills; and definite improvement in the capacity of the new insulation material (vacuum insulate panel with layers of wind-proof rigid mineral wool and EPS insulation) compared to the traditional. Carbon footprint of the new material is rather high in particular compared to the old mineral wool. Lesser heating energy is consumed over the calculated period of 20 years, and with the assumed energy cost the overall LCC is about equal for old and refurbished structure. Concept number 2 by VAHANEN – C1 Re-SOLAR is an innovative solution for both temperate areas with dry hot summer; and for cold areas without dry season and with cold summer. The major innovation is in the structure where solar radiation is utilized both for generation and conservation of energy – while the solution collects energy it also prevents overheating of the building. The concept includes ventilation air handling and thus can be used for a more controlled indoor climate, including air purity aspects. As the concept is novel there is no practical experience of its performance. Calculated en energy savings (both fossil and renewable) are significantly higher in the cold area applications. In terms of carbon footprint only the chance in temperate areas with dry hot summer are modest when the material production is taken into account; but in cold areas without dry season and with cold summer the concept yields benefits in carbon footprint reduction. Life cycle costs change fairly scantly. External appearance changes significantly. Load bearing is arranged to the existing structures, and also that need design solutions. Concepts number 3 and 4 by VAHANEN – T1a. ETICS applied to sandwich element and T1b. ETICS applied to sandwich element internal layer with smooth element surface have a wide potential for markets: the intended use for very common structure in the Northern European building stock that is to be refurbished in the coming couple of decades needs such solutions that are applicable in considerable scale. Here the applicability is good because the materials are common and the needed construction work is familiar in large areas (including Russia). Despite the traditional features in it, the concept can be applied in an architecturally intriguing way – a feature supporting the visual upgrading of the buildings and areas. Providing good quality workmanship is used to create the desired finish then the refurbishment method should enhance the external appearance of a building. The concept 5 and 6 by VAHANEN – T1c. ETICS applied to insulated panel RUS and T1d. ETICS applied to solid panel RUS are in particular aiming at the export markets as the panel type concrete wall that has been very common since 1960 in Russia and previous Soviet countries is now approaching refurbishments. Furthermore the refurbishment method can also be used for solid concrete block walls. These concepts


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are plausible choice when the external surface needs refurbishment – and in particular, if architectural enhancement is a target for the building or the area. Carbon footprint gets lesser in a meaningful way, and so does fossil energy consumption; but the non-renewable raw materials consumption is unfavourable. The impact on life cycle costs is smaller in T1c and clearer in T1d. The concepts EKK1 Filling brick wall cavities with carbamide resin foam and EKK2 Thermoreflective multi-foil outer insulation of brick wall with controllable ventilation air gap before insulation are both targeting a very acute refurbishment need with either a relative simple and affordable or a more sophisticated and expensive option. The concept EEK1 is economically and technically very feasible and provides benefits both in economic and environmental sense to a large building stock on a large geographic area. EEK2 is more demanding in technical and economic sense, but provides for demanding clients opportunity to enhanced indoor air quality and comfort along with the necessary ventilation upgrade. Exterior refurbishment of wooden frame walls - with a flex system board insulation by TOBB is a concept especially appealing in the Nordic countries but applicable in the wood buildings of continental Europe. The environmental and economic outcomes are at their best in the north and decline towards more southern location of the building to be refurbished. This technique will therefore be a competitive alternative to the conventional refurbishment choices. Concept number 1 by ONEKA – Transparent insulation is an intriguingly innovative option to provide improved heat insulation, solar gains and comfortable light. It is aiming at a niche market but there it can be an attractive option. It reduces energy demand through better U-values, by acting on the wall or on the windows and increases solar gains through the wall. This system will always modify the external image of the building, so architects have an opportunity to upgrade appearance in the refurbishment. Both LCA and LCC are improving in all (honeycomb, glass capillary layer, and aerogel) options. The concept number 1 by SGG – SGG 1: External insulation of solid rubble stone wall with vapour-open natural insulation material and ventilated timber cladding is the first of the solutions for special solid thick wall (400 – 1000mm) built with two faces of stonework. The concept number 2 by SGG – SGG 2: External insulation of solid rubble stone wall with semi-vapour-open mineral wool insulation material and acrylic render ; I Concept number 3 by SGG – SGG 3: External insulation of solid rubble stone wall with expanded polystyrene insulation material and acrylic render; and Concept number 4 by SGG – SGG 4: External shelter of solid rubble stone wall with unventilated dark-coloured steel sheet cladding are all targeted to external walls where in their original state no insulation has been fitted in the structures. In these concepts the method of insulating removes wind and rain from the external face of the stonework. It closes the air gaps. It reduces energy consumption by allowing the thermal mass of the masonry to become dry and warm, and greatly reduces heat loss through cold bridges. Concept number 5 by SGG – SGG 5: Internal insulation vapouropen of solid rubble stone wall with lime-sand pointing outside is aimed at cases a where the external appearance of a pointed masonry wall must be retained for aesthetic and/or historical reasons, insulation must be installed internally. All these SGG refurbishment concepts significantly reduce the needs for heating energy. The common feature is the intention to conserve the cultural heritage while making the buildings habitable with reasonable comfort. Often these solutions utilize ecological


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materials in an innovative way. The potential market is very limited but also very valuable in cultural and historic sense. As a conclusion, the provided concepts largely cover the climatic zones in Europe with feasible refurbishment solutions. The dissemination efforts will bring awareness of the possibilities with the developed and well analysed refurbishment methods to the interested parties in many European countries. The proper analysis of each concept allows justified choices and decisions based on realistic expectations of the performance over time. Solutions for sustainable refurbishment are offered for large building stock refurbishments such as the needs in Eastern Europe; and also to innovative niche markets and quite unique cases. The results show that it is not profitable to improve the thermal insulation of an external wall if the outer layer of the wall doesn’t need repair. So the concepts show the way to improve energy-efficiency in economical ways in connection to demanded refurbishments.


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19 Summary Company concepts for sustainable refurbishment have been developed into partner specific methods applicable to their own domains and further markets in particular in the Eastern Europe markets and the markets for specific cultural conservation (historic buildings). The companies that have developed the sustainability driven refurbishment concepts are Vahanen with 6 concepts; EEK with 2 concepts; SGG with 5 concepts; TOBB with one; and ONEKA with one. The concepts are viable both technologically and in sustainability (LCA) with reasonable life cycle costs (LCC). Some of the concepts rely on fairly traditional materials used in the targeted market areas. This has the benefit of availability of the structural components and labour force able to do the construction works. Some have more demanding materials and require higher qualification of labour. As the starting point is the repair of the existing external wall. The wall types included to the company concepts are: -

Lime-sand brick wall; multi rise buildings and single family dwellings Nordic Europe Sandwich element panels; multi rise buildings typical in Nordic Europe Panels with mineral wool; multi rise buildings typical in Russia, Ukraine, Belorussia and Baltic countries - Prefabricated solid panels; multi rise buildings typical in Russia, Ukraine, Belorussia and Baltic countries - Brick walls with air cavity or decayed wool insulation; single- and multi-storey buildings in North European, Central (also Eastern) European countries - Wooden frame wall; detached and terraced house typical in Nordic Europe and also in the Northern Continental Europe - Cavity brick walls; single/detached family houses and multi-storey buildings in areas with dry, hot summer; and in areas with cold climate, without dry season and with warm summer - Solid thick wall (400 – 1000mm) built with two faces of stonework without insulation; single and multi-storey buildings in areas of mild, wet, windy climate The company concepts thus cover vide areas and high versatility of buildings raging from historically valuable items to massive industrially constructed quantities of standard buildings in various climates. The performance of each refurbishment concept was evaluated with calculus and simulation tools for the climatic conditions that the concepts are developed for. This report presents the results of these multifactorial assessments in numeric and graphical form, and discusses the applicability of these concepts with technical conclusions. Technical drawings are presented of the principal solutions.