adjacent to mixed use retail complex, transit hub and surrounded by ... connected by a parking and shopping podium. .... eastern city side of the city centre.
Sustainable Vertical Urbanism as a design approach to change the future of hyper density cities High Density & Not Highrise Ahmed Ehab Abdelsalam AEH, David Nicolson Cole & Khaled Dewidar 1
Sustainable Tall Buildings studio, Department of Architecture and Built Environment, University of Nottingham, UK. 2 Department of Architectural Engineering, The British University in Egypt, Cairo, Egypt. Abstract: This paper will mainly focus on introducing Sustainable Vertical Urbanism (SVU) as an approach for designing hybrid buildings and upgrading the public realm, making full use of the vertical dimension in hyper density cities. The article explores some more recent case studies of optimized quality density in US, Europe and Asia. The article set out to answer the questions since density is the key of sustainable urbanism, what are the drivers and different planning approaches in relation to establishing an optimal density? The article will analyse the outcomes of three different interviews done by the Author to specialists in the field of urban design, architecture design and construction developers. The aim of these interviews to study what is the ideal density model for tomorrows sustainable cities and explores how sustainable vertical urbanism could help us to create highly liveable, economical vibrant, mixed-use and resilient neighbourhoods of the future.
Keywords: Vertical Urbanism, Vertical public realm, City Vitality, Hyper density, Mixed use, Place making, new vertical Unusual functions
Introduction Urban density and mixed-use are the key aspects in determining sustainable vertical urbanism. Already half of the world land surface has been changed for humanity use. As more and more people live in cities, the cities have taken core stage as a key player in the future of human populations. The main challenge for cities in the future will be the integration between compactness, vitality and urban form. (Boyko CT,2011) The future of cities is also about diversity which requires varying urban densities for different neighbourhoods in different part of the city. The diversity of building scale and density types allows different demographic groups to choose how they would like to live at varying stages of their lives. (Rouse, 2018) Sustainable vertical urbanism increases efficiencies in urban infrastructure and services through shorter distribution networks. Higher density cities encourage reduced transit through shorter trip lengths, since most amenities and public transport are more closely located. However, making neighbourhoods more compact and dense needs careful consideration and a process of optimization to balance potential adverse effects; higher density is beneficial at appropriate locations, but not always in every case. (Lehmann, 2016) All urban areas have their particular social and climatic conditions as a result of complex urban microclimates, and density affects urban wind speeds. The interplay between higher density and the increased risk of the urban heat island effect (which increases cooling energy needs) must be properly researched and taken into consideration. Higher densities require an optimization process as higher densities can create challenges for planners and designers, for instance, to avoid over-shading, over-looking, loss of daylight and the loss of privacy, which demands clever design solutions. There are a number of other arguments against high density, which include the risk of increasing traffic congestion in the area and a potential increase in noise disturbance. (Lehmann, 2016)
Case Studies The following section describes the selected cases of new hybrid buildings in compact superblock in Singapore, USA and Europe that have introduced density each in their own way. These cases are compact and spatially complex models featuring medium to high density housing typologies. The following case studies deserves a closer look because they have successfully introduced denser housing models and tested new innovative typologies for SVU, where buildings, public spaces, urban greenery and new functions have been combined and intertwined. Sky Habitat Sky Habitat was designed by Moshe Safdie. The hybrid complex is located in the neighbourhood of Bishan, eleven kilometres to the north of Singapore central business district. The site is adjacent to mixed use retail complex, transit hub and surrounded by schools, and religious institutions. Sky Habitat is a thirty-eight-story residential hybrid complex, that explores the balance of high density living with sustainable vertical urbanism concepts of community, landscapes, gardens and daylight. The main concept of Moshe Safdie, was to reinvent the apartment building, to rethink the paradigm of how high density urban housing is built today. The naming of the building is a reference to his extraordinary housing complex in Montreal 1967, called Habitat. (Safdie, 2015) Figure 1. Sky Habitat Singapore, by: Safdie Architects. On the three-acre site of Sky Habitat, the traditional, conventional solution would have been to build a number of towers, two or three, to be separate extrusions as independent buildings connected by a parking and shopping podium. In Sky Habitat, there is one continuous structure, which is perforated and permeated by large openings and cascading terraces. There are bridges that connect the structure at three different levels. There are gardens at the sky and at the ground. There are private terraces or generous balconies for the apartments. The building steps up, almost like a hill side forming one continuous matrix of urban living. Safdie nostalgically references hill towns and villages of Provence or Italy, or the rock-cities of Cappadocia in which the scale of the individual unit or cave is perceptible. The traditional hill town appears to be made up of many individual pieces, which are clusters of houses each one with their gardens. The designer tried to achieve the more comfortable human scale, which gives individual identity within the building and in the share external space. Three bridging sky gardens connect the two stepping towers, creating a series of interconnected streets and gardens in the air, providing areas for common recreation and social interaction. The overall mass is open and porous allowing daylight and breezes to flow within the building. The stepping geometry allows every residence multiple orientation and private outdoor spaces. (Safdie, 2015)
Figure 2. Sky Habitat Singapore form development, edited by Author
Building Sustainability: “The denser you go the more challenge it is to achieve sustainability in other words what you can do in a scale of a cluster of town houses is very difficult to do as you go Forty, Fifty, sixty stories up in the air” says Safdie. The main challenge was to create a micro climate, that’s comfortable to respond with Bishan tropical hot climate. The building needs to maximize the breezes, which means that all the public spaces within the structure, should be enjoying cross ventilation. In hot tropical climate, you need to create shade and this building is also about creating shade, deep balconies which shade the façade. Solar shades on every individual window cut the sunlight from penetrating and heating the unit. The more shade you create, the less energy needed to spend in cooling down the unit and making it comfortable. (Safdie, 2015) In Sky Habitat2@Bishan, both these ideas are taken along in a literal sense. We see more planting in the building, and more trees supported by the various terraces. The more shade Safdie creates, the more is the sense that nature climbs up onto the building and creates its own place within the structure, acting like streets in the sky, with massive open spaces, distant views, and community facilities. At the ground plane, more than seventy percent of the site is developed into a series of lush gardens. They provide outdoor public spaces, walking paths, tennis courts and swimming pools. Two levels of parking are completely hidden by planting, so that the parking area does not dominate the view or block the sun. The courtyard is a ventilated space, where users can enjoy going for a walk through the whole network of walkways and bridges, from one part of the complex all the way to the other end, passing by community rooms, swimming pools, gardens, sitting areas and playgrounds. Users can do that at several levels, and this can become a part of user’s daily experience. Fathers and mothers can stroll around with their children in the building. Older senior citizens who want to spend time outdoor are able to find the appropriate space that suits them best within the building. Families can enjoy the food courts nearer the ground. (Safdie, 2015) The façade design helps to reduce the tropical heat. The two-meter cantilevered balconies, play a vital role in shading the windows, cutting down direct solar radiation. Each apartment is designed with balconies, and most of the apartments have two or three balconies. The balconies shift left and right, which gives the inhabitants a double height balcony space, and the entire façade becomes pixelated, breaking down the mega scale of hybrid building.
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Figure 3 Sky Habitat Singapore façade design, by: Safdie Architects
“The Design of Sky habitat hybrid comes at line of evolution and developments of design which we have been working for decades to bring together all these ideas of gardens, community spaces and privacy, of permeating the building with nature; all this is coming together as part of an evolution of seeking maximum level of liveability for high density urban housing” Safdie says. VIA57 West “Courtscraper” VIA57 west, introduces a new typology to New York skyscrapers, designed by BIG for the Drust organization. VIA 57W occupies a full city block between W57th and W58th street with direct views towards Hudson river park and water front. The construction started at 2011 and was completed at 2016. The thirty-two-story building has welcomed residents since May 2016. The CTBUH named VIA57 the best tall building in the Americas as part of its 2016 tall buildings award.
Figure 4. VIΛ 57 West, New York by BIG
The site has a beautiful location on the water, but is right next to a powerplant, waste management facility, parking garage and highway on the west side of the site. “it’s a beautiful location but it’s a very sort of industrial neighborhood” says BIG. The main idea was creating an oasis in the middle of the city, so the idea became like what happens when you combine a New York skyscraper with a Copenhagen courtyard. (Warmann, 2011) The form starts by placing the courtyard building next to the Helena57W tower, lifting up the north-east corner to four hundred sixty feet, to give Manhattan good residential density. From the highest point, it slopes downwards to maximize day light exposure to the south and the west, and also preserve the view of the river. On the north face, the windowed façade is saw-toothed to give residents a view to the Hudson River and the afternoon sunshine, with periods of morning sunshine along 58th St.
Creating this highly unusual new silhouette on the west side waterfront, like a completely distorted Copenhagen courtyard, is a major contribution to the favourable public perception of the building. The building comes all the way down towards a horizontal line at the ground on the west side, and then as it moves towards the east, it moves upwards in a vertical incline, creating a sort of south facing mountain slope, that traces the arc of the sun at the heart of it. Individual terraces are sunken in the sloping surface, creating a sort of vertical community like a mountain town in the middle of the city; a landscaped park in a courtyard lies at the centre. (Ingels, 2016)
Figure 5. VIΛ 57 form development by BIG
The VIA57 ‘courtscraper’ is a hybrid between the European perimeter block and the traditional American high rise. Most of the buildings contains residential units of different sizes with cultural and commercial programs at the street level and the second floor. The lower level of the building has a strong relationship to the courtyard. The lobby is connected directly to the courtyard, that invites residents and people to the public open space. The generous amenities at VIA57 includes lounges, gym, pool, play rooms, basketball court, golf simulator and movie screening room. Most of these amenities are placed around the courtyard to create a strong visual and physical connection between exterior communal public and the interior to enhance the urban life style within the building. At the upper level, the apartments are organized on a fishbone layout, orienting rooms towards the river view. Large terraces are carved into the façade to maximize the view and light into the apartments, while ensuring privacy between the residents. (Warmann, 2011) Residential apartments fish bone layout
Courtyard
Figure 6. VIΛ 57 apartment fish bone layout by BIG
Figure 7. VIΛ 57 residential floor plan edited by Author
Markthal Rotterdam Markthal Rotterdam is designed by MVRDV at a historical location at Binnenrotte, next to Blaak station and the largest weekly open-air market in Rotterdam. Markthal Rotterdam is the first covered market of the Netherlands that was opened in 2014. Markthal Rotterdam is a completely new concept the first building of its kind, a hybrid between Market hall and vertical housing. By using the apartments to create an arch that covers the market, a new public building emerges. Its shape, colourful interior and the height turns Market hall in to a unique spectacular icon in Rotterdam. MVRDV won a competition organized by the city of Rotterdam for the design and construction of a market hall at Binnenrotte. The city of Rotterdam wants to extend the existing open-air market with a covered addition. According to European future rules, the open-air sale of fresh and chilled food wouldn’t be permitted anymore. Moreover, the city want to augment the number of inhabitants in the city centre, and to create more capacity services in the area. The city demanded program housing, parking and a market hall asked for a logically fitting solution: two residential slabs with an economically constructible market hall in between. MVRDV had seen that these kinds of market designs are always dark especially in the south of Europe, as it will act as introverted building with little connection to the surrounding urban area. MVRDV’s vision was to create a highly public open building with good accessibility to the eastern city side of the city centre. The team decided to flip the two slabs and market vertically which lead to a larger hall with two wide opening towards the city. In order to make the construction more efficient a curve was chosen, within which is fitted elevator cores and added extra retail spaces to the lower floors. (McManus, 2015)
Figure 8. Markthal Rotterdam concept and sketch, by MVRDV
Markthal gives an important impulse to its surrounding area, which is strong contribution to the urban economy. Markthal with its daily fresh food market, shops and apartments creates coherent and connections in the neighbourhood that reaches a new centrality. The city of Rotterdam started refurbishing Biennenrotte square after the completion of Markthal to make it more attractive. Markthal is easily accessible by all means of public transportation as metro, bus and tram. Blaak train station is right in front of the building. In 2015 the city of Rotterdam constructed a recessed bicycle parking with space for 800 bikes. Markthal is also accessible by car, there are four underground parking levels offering 1200 parking places. (McManus, 2015)
Markthal is not only unique in its shape and size, but specially the way of different functions are combined together - the combination of an apartment building covering a food market with food shops, restaurants, supermarket and underground parking garage – mixed use of the sort that can only be found in Rotterdam. (ArchDaily, 2014) The building needs to be as open as possible to attract people and at the same time had to be closed due to weather conditions. Markthal is a building without a back side, all sides of the building are accessible or shop windows. Inhabitants reach their apartments through six separate entrances, leading to elevators and double helix flight stairs. Inhabitants also have storage rooms and shared bicycle rooms in the basement. Due to the curved structure, the elevator lobbies gradually shift size and location, floor by floor. At the ground floor elevators are located at the inner façade, at the top floors towards the outer façade. Each elevator hall services a maximum of four apartments and have windows to the market and large glass fronts towards the outside.
Apartments
food shops, restaurants & market hall
Car Parking
Hyper Market
food shops, restaurant Figure 9. Markthal Rotterdam section, by MVRDV, edited by the Author
Markthal received a BREEAM ‘Very Good’ certificate. The building is connected to the city heating and a thermal storage system underneath the building which will also heat and cool a number of adjacent buildings in the surrounding area. The various functions in the building can exchange heat and cold. For the hall, itself extensive research was conducted to create a comfortable interior climate with an extremely low energy use. The hall is naturally ventilated, underneath the glass façade fresh air flows in. It rises towards the roof and leaves the hall through ventilation shafts in the roof. Half the apartments have windows to the market; these windows are triple glazed to avoid sound or smell nuisance.
Figure 10. Markthal Rotterdam Interior, by Arno Coenen.
Experts Interviews Achieving sustainable vertical urbanism is a critical issue, which has many perspectives of how the community see the design of high-rise buildings, and how they see the design of current cities. These perspectives are different, from the view of urban designers, planners, architects and construction developers. This chapter will be discussing the outcomes of expert’s interviews of different fields. The first interview was with Tim Heath, the Professor of Urban Design at the University of Nottingham, and the author of Public places - Urban Spaces book. The second interview was with John Prevc partner at Make Architects and has been responsible for a number of high profile regeneration projects. The third interview was with Dik Jarman an Australian lecturer, Studio 505 Director and innovative designer, with over twenty years’ experience in architectural practice and professional film making.
Tim Heath
John Prevc
Dik Jarman
Tim Heath interview outcomes (Professor of Urban Design) People’s fear about tall buildings depends on where they are in the world. In Europe, US and UK, there is still a legacy of failed projects, putting people into buildings they didn’t necessarily want to be in. People worry about the isolating exclusivity of tall buildings; they worry about access and accessibility. With the recent fire in the Grenfell tower in London, that will affect people perceptions about the safety of living in residential tall buildings. Particularly from the social housing perspective, in the UK there is always been a tradition of people living in houses with gardens. The concept of living in apartments is still relatively new in the UK, and still a lot of people are inspired to have a home with a garden, which doesn’t equate to what they will have in most high-rise buildings. This perception is slightly different to Europe where there are already more people living in apartments and flats in the urban centers. Generally, the most permanent thing is the risk of fire and safety, that people thinking of moving to a tall building would most fear. It’s possible to achieve new functions in to successful mixed-use developments. There are a lot of advantages to mixing uses and, getting these new functions in to tall buildings is a positive thing, especially in dense cities where land is a premium. These hybrid buildings should be highly connected to transport hubs as rail, metro and bus to reduce the reliance on private car. Mixed use tall buildings are the future, but they shouldn’t sit in isolation, as people will still use cars to get to or from them. Mixed use hybrids, need to be integrated in to a proper master plan to be a part of a city, which will help the whole city to become more sustainable. As we are moving towards vertical mixed-use hybrids and creating public realm, urban designers should have the role to play. They should have significant impact on place-making within the building and also think about the building and its external context. The main obstacles facing vertical urbanism are cost, affordability and planning restrictions. “we have the knowledge, skills and technology to build and design vertical
hybrids, physically it’s not an issue, its more about policy, restrictions and public perceptions”. Form and organization of high rise buildings will affect the users and the vitality of the city. When you get different uses within the building, the way they move around the building will change quite significantly. In tall office buildings, generally between 8 and 9 am, there are a lot of people arriving, and between midday and 2 pm, there are people going out for short lunch breaks; again between 5 and 6 pm, people are leaving the building, searching for transport. Thinking about how to manage that, and how it is organized in relation to the other uses in a mixed-use development, needs to be designed carefully, to have efficient circulation, and to make people want to use that building; thinking similarly, with the public transportation infrastructure, about the impact of that building and the number of users on the infrastructure. The local transport system should be able to cope with the number of people at peak times. There are potentials to create vertical mixed-use streets, but we need to think to its impact on existing horizontal streets. Vertical streets shouldn’t kill the existing streets, by putting people away to isolated areas; this needs to be considered carefully. Creating a fantastic vertical street and rendering the street outside dead will result in building isolation and failure. Successful mixed-use streets are the new extension of successful public vitality streets, which always starts from the ground. John Prevc (‘Forget about height look at density’) When you build on a quite small plot and your building is a mixed-use complex, the main challenge is achieving a good net to gross ratio, as multiple users demand their own cores and separate lobbies. Most of the different functions, generally, don’t wish to share same service cores for practical reasons, privacy and security. The biggest building planning issue will be trying to make the cores work in a slim tall building. The other concern is servicing the multiple functions of the building. The vertical services aspects are different from the ones horizontally. Horizontally we have roads along which trucks and vans come and deliver. If you think you are delivering a lot of stuff high up a building [like vertical farming or retail], it will be economically expensive. It won’t be a net space, it’s part of the gross space that [rental-wise] is thrown away [unless specialized functions have custom rental contracts]. You should be commercially clever, to try making tall buildings of multi-functional type that will work. One of the vertically mixed-use buildings, that the MAKE company did was the Cube of Birmingham. The Cube is a multi-functional building with underground car parking, retail stores, offices, residential, hotel and at the top, there are restaurants and bar area. The variety of mixture was exceptional in any building. It’s an incredible building, and it took an incredible client to do that. The main challenge is the high level of cost and reducing the yield, as you are not selling as many square feet because of the cores and the service area. “We as a human being, our DNA hasn’t changed in many millenniums. We are [genetically] the same people who were historically living in caves. We like to be on the Ground, we don’t mind being on a hill on the ground, as it still the ground, it gives us advantage point for security reasons, we can look over the landscape, and make sure no one is going to attack our castle.” “It’s a culture change; we are adapting to it, but they [tall buildings] are not in a normal situation. If you ask anybody what sort of house do you like to live, generally the answer
will be a little house, with garden on the ground. So, making the vertical more like ground is a great idea but it has many challenges to be successful”. Projects in Singapore are successful where there is green nature on the façade, on the balconies, on the roof. Spaces are given away to eco-green, because green sells. Green is something that people want to buy into, and they are prepared to pay extra money for [the lifestyle enhancement of] that green balcony and green view; vast green areas at high level are economically expensive to achieve. The form in tall buildings has two perspectives; firstly, from the perspective of the city and its relationship with the surrounding. Secondly, from the perspective of the user and its view out of it. From the city perspective, there are too many buildings trying to assert their own identities. They just have complex forms, to be different to sell, and to satisfy the design team’s ego. “Vertical streets are still slightly utopian here in London; in Hong Kong it is possible, as they have high level street walks, connected with shopping malls”. There is a massive difference between tall buildings and the hyper dense environment; you can have just as many things going on. An extra square meter of plan, multiplied many times within a vertical hybrid can produce a better environment than just going taller by many storeys. In my talk with the CTBUH, it was all about vertical urbanism not just about being tall. They start to realize it’s about density not about height. Dik Jarman Interview outcomes What people most fear about tall buildings depends on different perceptions, according to their culture and habits. When we think, as an example, of British perception, it will be the sense of loss of what they already had, like losing the historic nature of London. They can be losing what London is, its low-rise significant buildings, with historic importance; the sense of loss of who we are and where we are. The fear of hyper density is ending. Although too many people are scared of hyper dense cities, as they think that the quality of life will go down, it seems that hyper density brings a whole lot of good. Hong Kong has the smallest car ownership on the planet, and it’s one of the highest population density spots. They have a great transport system, with buses, walkways and MTR. You can get a train anywhere within a minute; the thing with trains are that there are no traffic jams. A mass-transport system is quite different from mass-driving cars. There are many benefits that comes from hyper density, which most people don’t understand. People fear a change that makes a reduction in quality of life; this may not be true if you balance to the vibrancy, efficiency, escalation and vitality which hyper density brings to the city. Many of the modern cities now are very lonely places, with a lot of poor urban planning in the way they arrange buildings. There are many tragic stories, of people who died in their apartments and they found them a year later, because their neighbourhoods didn’t know them. There is a lack of social interaction within buildings and with the residents’ relationship with the city. That’s a failure of city planning; city planners should start bringing communities together, which could be achieved in vertical urbanism in the way of organization. The mixeduse organization should help community networks and encourage new interactions with different communities. If you think about driving your car to your vertical home, into an underground car park, then getting a lift to your front door… that kills all the opportunities, which used to be walking
down the street, saying hello to someone; that is the richness vertical urbanism should provide. Vertical hybrids should be actively designed, understanding spaces and the node points where people cross; that creates a place where people can sit down and take a break or rest in an open space, which will maximize the opportunities for these meetings and greetings. That’s the way form and organization can help to facilitate better. Hybrid buildings could change people perception about tall buildings, if their perception is now that buildings don’t have much public space. Good architecture can change people’s perception and fear of tall buildings. That’s exactly what happened in Melbourne, where certain large buildings as the new Melbourne museum, the new Melbourne exhibition center and couple of others showed that there is really exciting new architecture around them; so public started to take interest. There is an Australian architect Fender Katsalidis who was doing tall developments, which was really interesting in its shape, materiality and lifestyle components, which people started to realize that tall buildings didn’t have to be glass office boxes, they could be great places to live. There is a whole series of examples, where the built architecture changed people’s opinion. Then slowly, as people’s opinion changes these buildings accelerate, because the public want more of that kind of designs. You can only sell what the public want, but you have to get them to change their opinion first. Building tall is always expensive, and there are better ways to design it. We can build very well, richly hyper dense, and height is one part of the solution. Height is not the only solution. They need to re-design as hybrid buildings, to have more flexibility with the rest of the community and be part of the city matrix. It’s very easy to build a boxy high-rise office building. Building a quality building which has range of functions, that’s really expensive; you need a client who is ready and willing to do this for the community, like government buildings or good developers. You need developers who want to make the greenest building in the world. Vertical hybrids need architects who have the understanding of how to design them well, as it involves a whole range of design factors. The more we do, the more we understand them. Town planning and government can get behind these factors, as vertical urbanism is important for the community and for raising the quality of life. In long term, these hybrid buildings will be the future investment. Conclusion When you are densifying an area that is already dense, there is a question as to whether the existing infrastructure can cope. One other challenges city face in their densification strategies is public resistance against higher densities. If SVU frame work is considered higher density will increase liveability as can be seen in cities as Singapore, Barcelona and London. Higher density living can be acceptable for residents as long as these developments provide green sky parks and urban vital spaces. (Akers,2010) SVU design should include high tech design solutions as well as low tech alternatives. The fundamental and organizational aspects of sustainability should consider building form, structure vitality of different functions, place making, context specific issues (Climate and Culture) and passive house solutions. (Lehmann, 2016) High Quality sustainable vertical urban design can alleviate negative perceptions of density at the metropolitan scale. Higher densities require new better housing typologies a wider range of compact housing model and innovative design solutions that integrate urban morphology
and the quality of public spaces. Landscaping, parks, green roofs and the design of community spaces must be important elements from the outsets of each development. (Edwards,2014) Some of todays thinking about SVU in Singapore and Sydney could translate to other cites and inform new approaches to increase the inner-city density and sustainable urban mobility. This Article set out to answer the question since density is the key to sustainable vertical urbanism what are the drivers to consider? (Lehmann, 2016) The analysis of the case studies explained the different planning approaches and urban form influences very different density outcomes. The outcomes of expert’s interviews discussed how different parameters as building scale, density, public perceptions, public space connectivity and vertical public realm can drive the outcomes of hybrid buildings, however these parameters will need to be studied more in depth and more future research is needed with consideration of local context, for a better understanding of the optimal density level. Acknowledgment The author wishes to thankfully acknowledge the numerous reference resources for preparing this Article; the valuable suggestions of the Conference reviewers in improving the quality of the manuscript are greatly appreciated. A special thanks to MAKE Architects and John Prevc for his time and discussion about vertical urbanism. The author would like to express his sincere gratitude’s to Prof. Tim Heath and Prof. Dik Jarman for their interviews. References 1. Akers-Jones, David (2010) ‘Foreword’. In: Edward N (ed) Designing High-Density Cities. Earthscan, London 2. Alexander C, Neis H, Anninou A, King I (1987) A New Theory of Urban Design. Oxford University Press, Oxford. 3. Bramley G, Power S (2009) Urban form and social sustainability: The role of density and housing type’ 4. Boyko CT, Cooper R (2011) Clarifying and re-conceptualising density’. Prog Plan 76:1– 61 5. Chakrabarti, Vishaan (2013) A Country of Cities. A Manifesto for an Urban America. Metropolis Books, New York. 6. Density Atlas (2011). MIT web resource, http://densityatlas.org/ 7. Edwards, Brian (2014) Rough Guide to Sustainability: A Design Primer (4thedn). RIBA Publishing, London. 8. Heath, T., 2017. Sustainable Vertical Urbanism [Interview] (28 July 2017). 9. Ingels, B., (2016). VIA57West. [Online]Available at: https://www.youtube.com/watch?v=LKSTB5Ie_HM [Accessed 12 March 2018]. 10. Jarman, D., 2017. Sustainable Vertical Urbanism [Interview] (15 August 2017). 11. Lehmann, S.,(2016). Sustainable urbanism: towards a framework for quality and optimal density.. Future Cities and Environment, Volume 2, p. 8. 12. Pont MY, Haupt P (2010) Space matrix: Space, Density and Urban Form. 001NAi Publishers, Rotterdam. 13. Prevc, J., 2017. Sustainable Vertical Urbanism [Interview] (10 July 2017). 14. Rouse, M. R. a. D., (2018). Dependency model: reliable infrastructure and the resilient, sustainable, and livable city. Sustainable and Resilient Infrastructure, 3(3), pp. 103108.
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