Two favourite classics:

Bernard Rudofsky, Architecture Without Architects: A Short Introduction to Non-Pedigreed Architecture

Baruch Givoni, Climate Considerations in Building and Urban Design

Two very short ‘must-reads’:

Camilla Ween, Future Cities–All That Matters

Adam Ford, Mindfulness & the Art of Urban Living

1. Our single, bounded planet

There are limits to the rate at which the planet can support food production (due to availability of land, sun and water), cleansing of air, resource extraction and waste processing in relation to the ever-increasing global population. The international, non-governmental body the WWF estimates that three earths would be needed to support a population where all nations’ consumption and waste-generation patterns conformed to those of the UK today. Pooran Desai and Sue Riddlestone, in Bioregional Solutions For Living on One Planet (2007, p28), conclude that six planets would be needed if globally we consumed at US levels (the WWF figure is four). Viewed in a different way, it has been stated by the Global Footprint Network that today the earth takes one and a half years to regenerate what we consume in one year. There is much detailed discussion and data on national ecological footprints available on the website of the Global Footprint Network and a good source for global population projections is the United Nations Population Division.

2, 3 and 4. Sustainability: definitions and perspectives, ethics and values

In an excellent introduction to the subject of global human sustainability, Peter Jacques, in the primer Sustainability–the Basics (2015, pp1–14 and 39–41), confirms that there is no single, positive definition but suggests that, at one level, to sustain something is simply to keep it going. The author describes (p41) ‘weak’ sustainability (focused on economics, assuming the market will find solutions) and ‘strong’ sustainability (focused on ecology, requiring substantial changes in behaviour). There is a very useful glossary of terms in this book (pp205–13). There are many definitions of sustainability in relation to the built environment, and Jeremy Gaines and Stefan Jäger, in their Albert Speer & Partners–A Manifesto for Sustainable Cities (2009, p16) suggest that sustainability means acting locally while thinking globally, a phrase in common usage today. Aiming at greater precision, Daniel Williams, in Sustainable Design–Ecology, Architecture, and Planning (2007, p3), tells us that sustainability is achieved by using local, renewable resources. The author points out that sustainability must be embedded in the design process (p14) and in Chapter 2 introduces the characteristics and processes of sustainable design, with a very clear and helpful list of criteria that all projects should achieve (p21). The UK Building Services Research and Information Association (BSRIA) tells us that sustainable construction would embody the following principles:

• Minimising non-renewable resource consumption
• Enhancing the natural environment
• Eliminating or minimising the use of toxins

Sustainable design is a multidisciplinary process that must start at the conception of a project, and which cannot be ‘bolted on’ later. This is true for new-build, retrofit and interior work. Lisa Tucker, in Designing Sustainable Residential and Commercial Interiors–Applying Concepts and Practices (2015, p2), confirms also that the whole design team must be involved.

Many authors speak of ‘ecological design’ when they refer to sustainability, indicating the prominence given to ecological and environmental issues. But sustainability is also viewed as the ‘triple bottom line’: social, economic and environmental issues being balanced within its remit. A building will not be sustainable if, for example, it is ecologically sound but society cannot afford it or does not have the skills to operate it. In an important discussion of emerging trends, Brian Edwards, in the Rough Guide to Sustainability (2014, pp315–28), points out how society currently incorrectly values certain materials and products over others, reminding us that sustainability is a matter of ethical responsibility: for example, it is a professional obligation to source materials which have been won without the exploitation of ecosystems and human labour.

Definitions of sustainable development, and the history of attempting to define it, may be explored in sustainable urbanist Stephen M. Wheeler’s comprehensive and well-structured primer, Planning for Sustainability: Creating livable, equitable and ecological communities (2013, pp30 and 31). Wheeler’s preferred definition (his own) is: ‘Sustainable development is development that improves the long-term health of human and ecological systems.’ Darko Radovic, in Eco-Urbanity (2009, pp9–16), contends that both the ‘eco-sphere’ and the ‘socio-sphere’ are currently threatened, but a central, optimistic theme of his essay is that sustainability and urbanism can indeed live together.

5. Design in six dimensions

There are many tools available to assist the sustainable design process. These tools include those used for analysis of options (of orientation, form, sun, wind, daylight, energy use, materials and waste) in a 3D-CAD Building Information Modelling (BIM) model as well as Life-cycle Analysis (LCA), in which the environmental impact of a material is measured. Varis Bokalders and Maria Block, in The Whole Building Handbook (2010, pp9–13 and 206–207), consider the applicability of various LCA methods, which will, when used with BIM, ultimately become the norm in sustainable design, and the BRE Green Guide to Specification uses LCA to evaluate common materials and components.

In the UK the government will require, from 2016, all its projects to be developed electronically through BIM, with the goal of enabling interdisciplinary design teams to reduce costs and carbon emissions through 5-dimensional project LCA. Eddy Krygiel and Brad Nies, in Green BIM; Successful Sustainable Design with Building Information Modeling (2008), provide a very accessible general account of the entire process from a practitioner’s viewpoint; theirs is still considered a leading text. Written by and for architects, François Lévy, in BIM in Small-Scale Sustainable Design (2012), provides a detailed, illustrated account of the design and documentation processes for all the key aspects of sustainable design with BIM. A 6D model is now described, in which the final built project information and operating instructions are handed to the client for interactive facilities management.

6. How ‘green’ is your building? (Shades of green)

Ken Haggard et al, in the Passive Solar Architecture Pocket Reference (2009, p80), explain that a ‘light-green’ building will have reduced electricity usage, while a ‘deep-green’ building would do this and more, but would also be conceptually different, employing an integrated design approach and focusing on passive and renewable techniques. In the Rough Guide to Sustainability (2014, pp209–20) Edwards (with Emanuele Naboni) provides us with his own ‘Blueprint for Green Design’, which deals with the briefing process, flexibility, passive design, simplicity in operation, longevity, renewables and ease of maintenance/upgrading.

Tom Woolley et al, in the introduction to the Green Building Handbook–a Guide to Building Products and Their Impact on the Environment Vol 1 (1997 Part 1), discuss the use of the term ‘green’ and provide their explanation of what ‘green building’ means: an uncompromising, holistic approach to sustainable design and development–although the authors allow that many of the common terms (green, sustainable, ecological, etc) are interchangeable. They set out a useful framework for green building, neatly summarised in four principles:

• Reducing operational energy use
• Minimising external pollution and environmental damage
• Reducing embodied energy and resource depletion
• Minimising internal pollution and damage to [occupant] health

David Clark, in What Colour is Your Building? (2013 pp83–231) defines a framework for designing green buildings from the perspective of low-energy use and overall low-carbon footprint, including materials choices.

Retrofitting is discussed by Janis Birkeland in Positive Development–From Vicious Circle to Virtuous Cycles Through Built Environment Design (2008, p40), with a very good diagram of the levels of sustainable retrofitting–from minimal to full-scale, regenerative ‘eco-retrofit’.

7, 8 and 9. The environment: definition, scales, local and global impacts

Thomas Carlyle is said to have coined the term ‘environment’ in his translation of Johann Wolfgang von Goethe’s phrase Umgebung in 1828, in an acknowledgement of humankind’s negative influence on the planet. A useful definition in ISO 14001 is ‘surroundings in which an organization operates, including air, water, land, natural resources, flora, fauna, humans, and their interrelation’. That interrelation takes place at all scales of the environment.

Researchers in the complex field of scale theory confirm that action at one scale of the environment impacts on other scales, and that those scales have both spatial and temporal parameters. In other words, short-term, local activities in relation to ecology (such as with climate change) have longer-term global consequences. Theory and practice indicate that those consequences may be felt in quite different locations to the source. Further discourse may be found in a study by Thomas Wilbanks in How Scale Matters: Some Concepts and Findings, in Bridging Scales and Knowledge Systems–Concepts and Applications in Ecosystem Assessment (2006, Chapter 2).

Desai and Riddlestone, in Bioregional Solutions For Living on One Planet (2002, p16), introduce us to their notion of thinking globally and acting locally, evidence of an understanding of the interconnectedness of the scales of environment, and the authors demonstrate, while describing their inspirational entrepreneurism, that what we do locally can have a positive effect globally.

10 and 11. Is the greenest building the one that isn’t built, or the one that is already built?

These two phrases have found their way into common usage, and both have their place in the green lexicon. Woolley et al, in the Green Building Handbook (1997, p14) are amongst only a few authors who discuss the crucial consideration of whether to build a new building, convert an existing one or, indeed, whether to build at all. Sometimes a new building is the only answer, and sometimes a hybrid solution fits best. Clark, in What Colour is Your Building? (2013, p186), concludes that if a building can be refurbished to significantly reduce operating energy then it is likely that refurbishment will be the lowest-carbon solution. Charles Lockwood, an author on green business strategies, tells us in the article Building Retro Fits (2009) that refurbishment is often seen as a lower-risk option, especially in a poor economic climate. Increased workforce satisfaction and productivity are seen as key benefits of retrofit. Edwards, in the Rough Guide to Sustainability (2014, p194) gives a useful table with typical timeframes for improvements to the various components and systems within a building, while reminding us that each upgrade provides a parallel opportunity for ecological/environmental upgrading. The need for a focus on retrofitting of the UK housing stock is discussed in detail by Sofie Pelsmakers in The Environmental Design Pocketbook (2015, Chapter 8) in a section that includes the measures to be taken, while Penoyre & Prasad (Sunand Prasad et al), in Retrofit for Purpose–Low Energy Renewal of Non-Domestic Buildings (2014), illustrate a combination of alternative thinking (such as rethinking of work patterns) and practical retrofit solutions. Bokalders and Block, in The Whole Building Handbook (2010, Chapter 4.3), provide information (pp611–24) on assessments, operational issues, maintenance cycles and details of low-energy-use refit techniques.

12 and 13. Longevity and flexibility

Paola Sassi, in the essential reference text Strategies for Sustainable Architecture (2006, Chapter 4.1), considers, with the help of case studies, design for longevity and makes a connection between longevity and flexibility. The author reveals (pp154 and 155) how a building might be designed to be flexible socially (such as for an increasing or decreasing family size) or because of new technologies. Bokalders and Block, in The Whole Building Handbook (2010, pp646 and 647), discuss the fact that built-in flexibility can be wasteful. Randall Thomas, in Environmental Design, an Introduction for Architects and Engineers (2006, p72), offers criteria for longevity of buildings, including:

• Design excellence, leading to public acclaim and therefore to a building that will be maintained
• High-quality and durable materials and design solutions, minimising the need for refurbishment

Further, related narrative may be found in Rule 19 and in Chapter 5 of the current volume.

14, 15 and 16. Carbon dioxide, fossil fuels, global warming and climate change: the influence of buildings, cities and people

The United States Environmental Protection Agency (EPA) has a useful summary of the global CO₂ position in the section Overview of Greenhouse Gases on its website. Clark, in What Colour is Your Building? (2013, p12), cites the very significant global reliance on fossil fuels for energy production, and he is one author who makes the point that people (occupants) have a major influence on building energy performance. Reduced energy consumption is the most important strategy (p180), and the author cites the human factor in one of his ‘10 steps’ to reduced energy consumption (p85). Bokalders and Block, in The Whole Building Handbook (2010, p277), explain that the variation in energy use in a household due to users’ habits is around +/- 50%.

Pelsmakers, in The Environmental Design Pocketbook (2015, Section 1.1), provides a neat overview of the relationship between the building industry, CO₂, global warming and climate change. The author reminds us that 50% of CO₂ from human sources is not reabsorbed by forests or oceans. The principle of Contraction and Convergence, an equitable means of reducing total global carbon emissions by considering per capita emissions by country, is also discussed (p15). For more detail, including the science and the political framework, Chapter 1 of the Rough Guide to Sustainability (2014, pp3–27) by Edwards gives an excellent account, including the specific challenges for the built environment. Urbanisation is the cause of the overall increase in CO₂ emissions (p9), and we are reminded that living patterns have a significant effect, as we consume more and expect more in our drive for an urban life.

17. We are an urban species

Dennis Rodwell, in Conservation and Sustainability in Historic Cities (2007, p112), states that environmental consumption and degradation are focused in the city, and Gaines and Jäger, in their well-structured and strongly argued Manifesto for Sustainable Cities (2009, p16), remind us that sustainability and urban planning are closely linked because, since the year 2000, more people live in cities than in rural areas. The trend towards urbanisation is set to continue. Edwards provides us, in the Rough Guide to Sustainability (2014, pp11–13) with a concise summary titled ‘The trouble with cities’, in which he identifies the nature of stresses placed on people and the planet in our cities and mega-cities. Clark, in What Colour is Your Building? (2013, pp13–15), describes the cycle that connects cities with climate change: swings in temperature leading to increased heating or cooling, requiring more energy, resulting in increased warming, contributing to further climate change. Rob Adams, in his rounded essay on the environmental successes achieved in the Australian city of Melbourne in Eco-Urbanity (ed Radovic, 2009, pp33–46), re-establishes the connection between the migration of humanity to cities and cities’ CO₂ levels. Strong city leadership is cited as a key strategic tool in reducing a city’s emissions, and an interesting aspect is the major benefit of relatively simple solutions: buying-in greener energy sources, switching to reduced-energy-use electrical and lighting equipment, and re-greening streets to create shade, reducing the impact of the Urban Heat Island (UHI) effect.

18. Transportation: the connection between buildings, cities and climate change

The United States Environmental Protection Agency (EPA) states that 95% of the energy used for transportation globally is derived from fossil fuels, mainly petrol (gasoline) and diesel. While buildings are the source of nearly half of all manmade greenhouse gas (GHG) emissions, Edwards reminds us, in the Rough Guide to Sustainability (2014, p7), that half of the remaining emissions come from the transportation we use in moving people and products between buildings. Professor David MacKay tells us, in Sustainable Energy–Without the Hot Air (2009, p121), that public transport is between five and ten times more energy efficient than car use. There is a very thorough chapter on the issues and solutions by Adam Ritchie and Randall Thomas in Sustainable Urban Design–An Environmental Approach (2009, pp21–30), in which the authors conclude that the aim must be to reduce the need to travel, using public, low-emission vehicles in a high-density, mixed-use city. Ritchie, in his introduction to the same book (pp 3–11), makes the important statement that density, transportation (or how we move around the city) and energy are linked, and that energy per capita decreases with urban density (p6). Transport energy, and consequently transport carbon, are further discussed by Clark in What Colour is Your Building? (2013, pp70 and 71). From a case study of an out-of-town office, the author concludes that transport carbon can be higher than carbon generated by the operation of buildings. In Chapter 9, Clark provides practical solutions for reducing transport energy, and here the author discusses emissions reductions from home working. Considering the other end of the journey, Desai and Riddlestone, in Bioregional Solutions For Living on One Planet (2002, p23), conclude that there is limited value in building energy-efficient housing if we continue to commute by car. The ‘Tribrid’ vehicle is defined in Ken Yeang and Lillian Woo’s Dictionary of Ecodesign: An Illustrated Reference (2010, p243).

Energy and carbon data for transportation may be found in the European Environment Agency’s report Energy efficiency and energy consumption in the transport sector (2012).

19 and 20. Design for adaptability and resilience

Adaptability is a key attribute of sustainable architecture, but it is rarely evidenced in built works. While flexibility, which is the ‘loose fit’ in Rule 13, refers to the capability of making short-term changes to fabric and systems, adaptability is the facility to accommodate larger, long-term change, such as a major change of use, or even a change of location. Often the two terms are used interchangeably in architecture. Today, adaptability is most often discussed in relation to climate change, although there are other dimensions to it.

Climate-change resilience of cities and their infrastructure (roads, railways and airports) has become a topic of increasing concern to governments and private-sector operators, with sea-level rise and extreme weather events a serious concern. In the book City Design: Modern, Traditional, Green and Systems Perspectives (2011, Chapter 3), Jonathan Barnett provides (along with a neat summary of the history of urban design) a useful depiction of the mechanisms and impacts of climate change on cities, with a particular focus on coastal settlements.

There is a relationship between adaptability and resilience because resilience might be planned for but not implemented initially, requiring adaptability in future. Bill Gething and Katie Puckett, in Design for Climate Change (2013, p115), identify the issues surrounding construction in a changed climate under the following headings:

• Structural stability (and the particular vulnerability of existing buildings)
• Weatherproofing, details and materials
• Site work

Pelsmakers, in The Environmental Design Pocketbook (2015, pp45–57), provides a chapter dedicated to design strategies for climate change. It contains helpful design checklists and discussion on the importance of future-proofing our buildings. Issues of durability of materials in relation to climate change are covered in The Ecology of Building Materials (2009, Part 1.1.2) by Bjorn Berge. The author reminds us (pp12 and 13) that there will be an acceleration of decay in wetter climates, and thermal stress and insect problems in hotter and drier regions. Building-materials choices must therefore be climate/region specific. An annual global forum, Resilient Cities, publishes its yearly congress reports containing information on climate-related incidents and success stories, including the outcomes of its building and construction forum.

21. Off-grid

One chapter headline in Vishaan Chakrabarti’s A Country of Cities–A Manifesto for Urban America (2013 p78) is ‘if you love nature, don’t live in it’, and the author states that urban living is greener and more sustainable than suburban lifestyles. Living in nature is not a sustainable solution: it requires more resources and results in greater land loss and a larger carbon footprint (p81). Desai and Riddlestone, in Bioregional Solutions For Living on One Planet (2002, p75), comment that self-sufficiency is an impediment to the creation of specialisms (such as craftspeople, artists and scientists) in a society. The notion of an off-grid lifestyle is thus controversial. Nick Rosen, in his thought-provoking and entertaining exploration How to Live Off-grid–Ever Wanted to Unplug From the Rat Race? (2007), defines a version of off-grid living characterised by turning away from society (p35) more broadly than merely in terms of energy. The author rightly points out that concern for the environment might be only one reason for an off-grid lifestyle, and is wise enough to question whether off-grid living can be more ethical than the alternative. The author struggles to find urban off-gridders. The World Bank estimated in 2015 that 20% of the world’s population, or about 1.1bn people, live without electricity, in locations, in mainly developing regions, where none is available. In some such locations, there is growing evidence of increasing use of small-scale renewable energy. Entirely off-grid buildings are unlikely to be achievable in dense urban situations, as there is simply not enough footprint available for the solar-power or heat-generation systems required, or for the scale of wind generation needed. See the narrative bibliographical notes for Rules 26 to 32 for more detail and references to the status of renewable energy in the urban environment.

22. The earth as source of all building materials

Brenda and Robert Vale, in their seminal work Green Architecture–Design for a Sustainable Future (1991, pp31 and 32), describe well the relationship between the processes of design and building and the finite nature of the earth’s resources, reminding us that ‘no material is used in building but has its source in the earth’. Berge, in The Ecology of Building Materials (2009, Part 1), provides an indication of the years of reserve for a large number of earth’s non-renewable resources; he also reminds us that the building industry is the second-largest consumer of resources after the food industry. To brush up on things geological (and, indeed, geographical and biological), this author finds invaluable the Dorling Kindersley Visual Encyclopedia (1996). Those wishing to delve deeper into the geological aspects of the subject will find instructive the text by Peter Fookes et al: Engineering Morphology–Theory and Practice (2007), which has excellent illustrations and descriptions of the nature and locations of sub-ground materials and structures (pp30–8).

23. Economy of resources

Berge, in The Ecology of Building Materials (2009, pp8–10), gives examples of areas in which designers can economise on the use of materials:

• Optimising the building design, including the size, to reduce the amount of material needed
• Using lattice and hollow structures rather than solid and massive ones
• Using lightweight rather than heavy materials (has the added benefit of reducing excavation and foundations)

Pelsmakers, in The Environmental Design Pocketbook (2015, p196), makes the observation that the structural elements of a building are both the most costly and highest in carbon emissions, and so deserve particular attention at design stage. Bokalders and Block, in The Whole Building Handbook (2010, p35), discuss options for lightweight beams, and the prefabrication and modularity of construction elements are two commonly cited methods for optimising resources and reducing waste. The WRAP (Waste & Resources Action Programme) website contains much useful information, and has an action plan for resource efficiency in the construction industry. Further commentary may be found in the narrative to Rule 44.

24 and 25. Embodied energy

Embodied energy describes the amount of energy used in the processing and transportation of materials. In fact, two terms are now in common usage: embodied energy and embodied carbon. The distinction is that a material might have been won and processed using renewable (non-carbon based) energy, so it will have the same embodied energy as the same material created with carbon-based energy but a much lower embodied carbon. Clark, in What Colour is Your Building? (2013, Chapter 3), provides an excellent overview of what the practising designer needs to know about embodied carbon, and of the relationship between embodied and operational carbon. The author states that, in an office building, more than half the embodied carbon is in the sub-and-superstructure. In Green Architecture (1991, p41), the Vales grappled with the difficulties of calculating the energy content of building materials, a problem that still exists today due to questions about what to include. There is a good overview of the pertinent issues in Berge’s The Ecology of Building Materials (2009 Part 1.2).

In one of the Australian Government’s excellent series of online technical manuals, Yourhome (5.2, Embodied energy), the authors point out that quantifying embodied energy is less important than adopting the design principles of longevity, durability and adaptability. The UK green-industry advice group Greenspec has tabulated the embodied energy of common building materials; however, for the designer, the energy intensity of whole assemblies is probably a more useful measure, and some Australian examples are given in the Yourhome technical manual 5.2. Thomas, in Environmental Design (2006, p73), gives a graph of the approximate embodied-energy content of the elements of a detached house, with concrete being the highest.

The Australian Government states that over 100 years the embodied energy of a typical home today represents 10% of the operational energy (Yourhome Technical Manual 5.2). The US Department of Energy gives the figure as 15%. As we move towards much more highly insulated and well-constructed buildings that follow passive design principles, we may shift our focus from operating energy to embodied energy.

The embodied energy of high-thermal-mass materials like concrete and brick is often debated in the subject literature. Pelsmakers, in The Environmental Design Pocketbook (2015, p174), estimates that it would take up to 25 years for a building to ‘pay back’ its embodied energy in high-thermal-capacity materials from operational energy savings. However, most authors on the subject remind us that there are benefits to employing thermal mass in a building, including thermal comfort (from temperature stabilisation) and operational energy savings from solar gain. The embodied energy of insulation products will be saved many times over by the operational energy savings brought by reduced heat loss. Edwards, in the Rough Guide to Sustainability (2014, pp163 and 164), discusses ‘residual energy’: the energy remaining in a material at the end of the life of a building, which should be extracted.

The Waste & Resources Action Programme WRAP has an information sheet with comparative carbon emissions for various transportation types, demonstrating that road transport is significantly more carbon intensive than rail, and that rail is more intensive than transport by sea.

Recurring embodied energy is a further theme, particularly in the literature relating to sustainable retrofit. The choice of durable materials is cited by Jean Carroon in Sustainable Preservation–Greening Existing Buildings (2010, p8) as a key factor in reducing the risk of needing to replace materials, resulting in a recurrence of embodied-energy input.

26 and 27. Low-energy architecture and renewable energy

There is a wealth of information on the design and operation of low energy-use buildings, including the first book in this series by Huw Heywood, 101 Rules of Thumb for Low-energy Architecture (2012). Detailed design strategies, with excellent illustrations, may be found in GZ Brown and Mark DeKay’s Sun, Wind and Light Light: Architectural Design Strategies (2001). For further practical design guidance and case studies, refer to Alison Kwok and Walter Grondzik’s The Green Studio Handbook, Environmental Strategies for Schematic Design (2007). Passive solar architecture is the theme of Haggard et al in the well illustrated Passive Solar Architecture Pocket Reference (2009).

Energy, whether obtained from renewable or from low-carbon sources, is used for heating and/or for electricity. Bokalders and Block, in The Whole Building Handbook (2010, Section 3.2), discuss the problem of electricity production in a sustainable society, pointing out that storage of electricity in a private supply system remains an impediment to use, although in some countries it is possible to take advantage of a form of feed-in tariff and various incentives for microgeneration. Pelsmakers, in The Environmental Design Pocketbook (2015, Chapter 12), provides detailed decision-making and design information on renewable technologies. The Energy Saving Trust in the UK is an excellent web-based resource, and the Green Building Bible Volume 2 (2006, Chapter 2) by Keith Hall and Richard Nicholls contains a good section on renewables for anyone wishing to obtain a technical overview of the options.

28. Renewable energy: water

Large-scale hydropower remains controversial due to its environmental impacts, but substantial quantities of electricity may be generated using it. Wave-power generation is still in its infancy, but offers the same potential globally as large-scale hydropower. Small-scale hydropower is often combined with solar power in many regions of the world where grid power is lacking: in many rural, mountainous places in winter, water flow rates are high but there are fewer days of sunshine. Bokalders and Block, in The Whole Building Handbook (2010, Section 3.2), divide the subject into hydro (using reservoirs and rivers) and wave power. In the first category, large-scale, mini- and microhydropower are covered. Further detailed information, useful for the designer, may be found in The Environmental Design Pocketbook (2015, pp392–4) wherein Pelsmakers provides some helpful figures for the head requirements and the space needed for turbine housing (9 to 18m²). Billy Langley and Dan Curtis, in Going with the Flow: Small Scale Water Power (2004), provide a wealth of practical detail and case-study-based design data, as well as a fascinating history of microhydropower, with a useful glossary of terms.

29. Renewable energy: wind

Coasts, lakes and mountains are the chief locations for large-scale wind-power generation using wind farms, which are often controversial. The Carbon Trust’s guide Small-scale Wind Energy Policy Insights and Practical Guidance (2008, p23), has good illustrations and identifies the best conditions and locations for wind turbines, whether building-mounted or freestanding. The Energy Saving Trust recommends taking one year’s worth of real-time wind-speed measurements before committing to microgeneration, and the trade association Renewable UK, in its consumer guide Generating Your Own Power gives production figures suggesting that a micro-turbine of 1.5kW might produce 1,000kWh annually. The UK Government’s Department for Energy and Climate Change, in a report titled Energy Consumption in the UK (2014, p7), states that a typical UK home consumes around 4,200kWh annually. Comparative global consumption indicators may be found on the website of the World Energy Council. Many commentators are less than enthusiastic about the use of small-scale wind; large commercial wind farms and community buy-in programmes are the only cost-effective solutions. There is broad agreement that wind-power generation is unsuitable for urban situations, as only very large arrays of turbines, needing much land, would be effective.

30. Renewable energy: the sun

Edwards, in the Rough Guide to Sustainability (2014, pp122–31), provides a balanced view of the state of the art in terms of photovoltaic (PV) power. He supports community-wide use of solar collectors (for heating, not electricity production) to heat large volumes of water, providing winter heating needs. He reminds us that today solar electricity is costly in comparison with fossil-fuel-derived power, and there are still questions about the long-term efficiency of PV panels. Solar electricity, like that produced by wind, may be intermittent. Bokalders and Block, in The Whole Building Handbook (2010, Section 3.2.4), provide detailed background information on the science and application of different types of solar cell (also known as photovoltaics, or PVs). Pelsmakers, in The Environmental Design Pocketbook (2015, pp408 and 409), introduces the relatively new PV-Thermal (PV-T) panel, which generates both heat and electricity.

Stefan Bringezu et al, in a United Nations Environment Programme paper Towards Sustainable Production and Use of Resources: Assessing Biofuels (2009, p13), confirm that population growth leads to a significant increase in land use for crop growth, and that any land for biofuel crop would need to be in addition to this. The report also discusses water, noting that global agriculture is currently responsible for 70% of all freshwater usage and that the development of biofuel crops would increase this pattern. A key message is that ecological and land-use issues must be addressed in any life-cycle assessment.

31 and 32. Cities and efficient, low-carbon energy sources

Hall and Nicholls, in The Green Building Bible Volume 2, (2006, Chapter 2), outline the available renewable energies in a helpful, general account with some basic system-sizing data. Clark, in What Colour is Your Building? (2013, Chapter 7), provides an excellent appraisal of the options available for renewable and low-carbon energy (heat and electricity). Although Clark’s focus is on energy sources for non-domestic buildings, the principles and themes are likely to be of interest and use to those working in other areas. System-sizing information is given for each type. Pelsmakers, in The Environmental Design Pocketbook (2015, Section 11.4), discusses the cost-effectiveness of different energy sources, and there are excellent calculators and checklists for the designer to use in deciding whether the various sources are feasible (Chapter 12).

Heat generated by traditional power stations is normally discarded, but there are ways of using it. Oslo operates a Waste-to-Energy (WTE) plant, incinerating the city’s waste and heating the city’s public buildings with the resultant superheated water. Demand is greater than supply, so the Norwegian capital now, ironically, imports waste from other countries. An alternative is to obtain energy from landfill, and there is debate about the environmental and financial pros and cons of each approach. The UK Government’s Department for Environment, Food and Rural Affairs (Defra) paper, Energy from waste: A guide to the debate (2014 pp20–3) explains that debate very clearly, and states that WTE will be a better environmental solution than landfill energy providing that the plant is efficient, that the waste input can be correctly sorted and that enough waste is available. Bokalders and Block, in The Whole Building Handbook (2010, Section pp345–51), discuss human-generated waste, classifying the types and the various disposal techniques, and they also explain the principles of waste incineration with energy recovery.

There is broad agreement within the subject literature about many of today’s key issues, which may be summarised as follows:

• The priority is reduced energy consumption
• Renewable energy sources are difficult to use in cities
• Investment in off-site, community-wide systems is the answer, particularly for wind and Combined Heat and Power (CHP)
• Wind is only effective at a macro scale, and not in cities
• Biomass potentially competes with food production
• Solar-thermal is generally more cost-effective than PV

33, 34 and 35. Choosing sustainable materials

36. Sourcing materials locally and globally

Berge, in The Ecology of Building Materials (2009, p20), writes of a shipment of lightweight concrete blocks transported from Norway to Korea, using three times the amount of transportation energy than their initial embodied energy, thus confirming that heavy materials should be sourced locally. Edwards, in the Rough Guide to Sustainability (2014, p162), recommends a reasonable distance for sourcing heavy materials not made on site (eg stone, aggregate and bricks) of 10km. Edwards believes that internationally sourced, specialised, lightweight materials and components combined with local, common heavy materials will form the basis of a new architecture. Howard Liddell, in Eco-minimalism–the Antidote to Eco-bling (2013, p91), challenges common assumptions about local materials, reminding us that each material and its application must be considered on its own merits as there might be alternative, overriding concerns that would outweigh transport-carbon considerations. Pelsmakers, in The Environmental Design Pocketbook (2015, p204), usefully comments that it may be justifiable to source reclaimed and lightweight virgin materials from a distance, but no further than 100km. The author reminds us that environmental credentials must be checked even for local materials, and an excellent checklist is supplied (pp196 and 197).

37. Suitability and durability of materials

For a very good overview of durability issues, Berge, in The Ecology of Building Materials (2009, pp10–13), discusses durability in relation to quality of materials, with an emphasis on using the right quality of materials in the right place. The Whole Building Handbook (Section 1.1.3) by Bokalders and Block is organised in such a way that the authors’ assessment of materials enables the designer readily to seek suitable materials for particular elements of a project. Damp is discussed in detail (pp174–7), with the causes and solutions given, and the authors state that 90% of moisture problems, which are damaging to human health and to buildings, are caused by faulty construction. The moisture properties of materials and moisture migration are also dealt with (pp104–6).

An overview of the basic properties, including weathering properties, of some of the most common architectural materials may be found in the Materials for Architectural Design 2 (2014) by Victoria Ballard Bell with Patrick Rand. The book is very well illustrated with global case studies, and the authors preface each material-specific section with the various factors to be considered.

Birkeland, in Positive Development (2008, p104), reminds us that durable non-renewable and inorganic materials may be associated with high embodied energy and waste, and that the earth takes an age to heal after their winning from its crust.

38 and 39. Water use and conservation, greywater recycling and rainwater harvesting

40. Sustainable drainage

A combination of rainwater-collection elements in the landscape (such as swales, channels, ponds, detention basins, reedbeds, green roofs and rain gardens) often form part of a Sustainable Urban Drainage System (SUDS). One key purpose of a SUDS is to slow surface-water run-off, allowing rainwater to filter back into the hydrological cycle and releasing pressure on the mains sewers commonly used to transport surface water. Pelsmakers, in The Environmental Design Pocketbook (2015, pp124–6), describes and illustrates such a system. Bolkalders and Block, in The Whole Building Handbook (2010, Section 4.1.2), provide further, very well-illustrated information on hydrology, detailed design proposals for permeable drainage surfaces and advice for snow management.

41. Greenfield or brownfield?

Pelsmakers, in The Environmental Design Pocketbook (2015, p62), points out the paradox that although vacant and previously used, a brownfield site might have developed a strong biodiversity. It is one of Williams’ criteria for sustainable development, in Sustainable Design (2007, p20), that new projects should ideally be built on brownfield sites within urban areas, whilst acknowledging that such sites need to be cleaned. Edwards, in the Rough Guide to Sustainability (2014, pp179–81), adds that in order to bring back into use the 20% of unused urban brownfield land a multiparty, private- and public-sector effort is needed. The advantages of using brownfield sites are given by Sassi in Strategies for Sustainable Architecture (2006, section 1.1, table 1.1.3, p17), along with another warning about the importance of managing the clean-up. Bolkalders and Block, in The Whole Building Handbook (2010, p517), provide a description of the complex and expensive methods used in the restoration of brownfield sites, reminding us that there are three basic approaches with respect to any contaminated earth:

• Removing it to landfill
• Cleaning it in place
• Removing, decontaminating and replacing it

André Viljoen et al, in Continuous Productive Urban Landscapes: Designing Urban Agriculture for Sustainable Cities (2005, pxix), state that brownfield sites are suitable for urban agriculture.

42. Banish construction waste

Ritchie, in Sustainable Urban Design (2009, Chapter 9), defines the problem: we have become used to an almost-invisible, linear chain of activities, whereas the sustainable process would be cyclical, with resources being returned into the construction stages of other projects. Edwards considers how to design for waste reduction in the Rough Guide to Sustainability (2014, pp172–4), the main messages being: ensure that waste is designed out, specify the highest possible percentage of recycled content in materials and components, specify reused materials where possible and design for easy dismantling. The Royal Institution of Chartered Surveyors, in a paper of proceedings titled Strategies for Reducing Construction Waste to Landfill in the UK (2012), noted two key findings:

• One third of construction-industry landfill waste emanates from architect’s decisions
• The greatest source of waste produced by contractors remains poor storage and handling of materials

The WRAP (Waste & Resources Action Programme) website is well organised and has useful sections on waste prevention and reduction. Bolkalder and Block, in The Whole Building Handbook (2010, p6), urge us to check that during the transportation phase of a material’s life, distributors will take back packaging material. Birkeland, in Positive Development (2008, Chapter 4), challenges the conventional approach to waste, taking a holistic, ecology-centric standpoint.

43. Thinking ‘back to front’

Michael Braungart and William McDonough first proposed a new way of thinking about design processes in their influential and highly accessible book Cradle to Cradle–Remaking the Way we Make Things (2009). The idea, as it applies to the design, construction and demolition of buildings, is that at the end of their useful life buildings (and every other manufactured product) should be capable, by good design, of being broken down into useful constituent parts and resources with no loss or waste. Often termed Life-Cycle Assessment (LCA), Edwards explains its processes in some detail in the Rough Guide to Sustainability (2014 pp65–70). By considering the whole-life material, energy and waste flows, we can determine and mitigate environmental impacts at the outset. The future of sustainable design is linked with the development of BIM, Building Information Modelling techniques in which the co-location, assembly and disassembly complexities of components and their materials can be readily analysed and good design can anticipate planned de-construction and reuse.

44. The four ‘R’s

Liddell, in Eco-minimalism (2013, pp39 and 40), simply states that recycling is a last resort. Pelsmakers, in The Environmental Design Pocketbook (2015, pp204–9), provides a concise summary with recommendations on building materials’ suitability for reclamation and recycling, and the section includes an excellent ‘Designing for deconstruction’ checklist. The idea of deconstruction (sometimes referred to as ‘unbuilding’) is gaining ground, for it is an issue with a close association with the idea of life-cycle approaches to the design, construction, dismantling and reuse of buildings and their components. Reclamation (rather than recycling) of bricks and other building materials is the theme in the Green Building Handbook by Woolley et al (1997, p59). The authors remind us that the energy stored in a brick is retained if the brick is reused, but lost if the brick is crushed for use as hardcore.

Reduction of resource use and the recycling of waste products from production are themes in The Ecology of Building Materials (2009, Part 1.1) by Berge. The author writes on the benefits of standard, monomaterial components (pp16 and 17) for ease of reuse and reduced wastage, as well as the possibilities for disassembly within the different ‘layers’ of services, structure and skin, which require renewal at different times in the building’s life. Urbanist Stephen Wheeler, in Planning for Sustainability (2013, p121), proposes further ‘R’s: ‘repurpose, research, rethink, resist and redistribute’.

45 and 46. Ecosystems and biodiversity

The UN General Assembly declared 2010–2020 the Decade on Biodiversity, hailing an era of international effort to tackle species loss and ecosystem damage. Not so long ago the secretariat of the UN Convention on Biological Diversity (UN CBD) lamented the fact that few people even knew what biodiversity was, partly because the language used to describe it (even by the CBD itself) was unintelligible. This huge and complex subject is becoming clearer, and bioIogist John Spicer, in Biodiversity: a Beginner’s Guide (2006, p2), neatly distills the myriad definitions of biodiversity into the phrase ‘the variety of life’. Biodiversity (biological diversity) is also described as a reflection of the number and variety of living organisms in an ecosystem. The CBD, and its excellent website, contains a vast resource of information on biodiversity and ecosystems. Biodiversity loss is explained well in the CBD’s very readable booklet Sustaining Life on Earth (2000, pp5 and 6). The importance of traditional knowledge and practices is revealed (p15); it remains true that indigenous populations understand and rely heavily on biodiversity. The ‘goods and services’ provided by ecosystems are listed in the factsheet Living in Harmony with Nature (2010, p2) on the CBD’s 2010–2020 website, and these include: providing food, fuel and fibre, and provision of materials for shelter and building.

Earth’s ecosystems exist within the ecosphere, and earth scientists describe the four most recognisable domains that make up the ecosphere as:

• Atmosphere–the gaseous layer
• Biosphere–all life on earth
• Hydrosphere–all water
• Geosphere–the solid matter of earth

Biodiversity means species, ecosystem and genetic diversity, and it is clear that the ecosystems we are dependent upon are sustained by biodiversity. Naeem Shahid et al, in The Functions of Biological Diversity in an Age of Extinction (2012), examine the state of play in their complex field, which seeks to understand the relationships between biodiversity and ecosystem functioning. Christina Von Borcke, in Sustainable Urban Design (eds Ritchie and Thomas, 2009, pp 34–6), discusses the importance of the diversity of plant species, which attract wildlife, and reminds us that we should aim to create varied habitats both within and connecting our cities and buildings. Local, native species are often more successful in attracting wildlife and being resilient to regional climatic conditions. The importance of connectivity between habitats is discussed by many authors, including Anne Beer and Catherine Higgins, who, in Environmental Site Planning for Site Development–a manual for sustainable local planning and design (2000, p297), consider the use of existing features such as river corridors. The authors explain how improved recreational green space can also achieve enhanced biodiversity. Eco-passages are described in the excellent technical manual by Kelly Gunnell et al, Designing for Biodiversity: A Technical Guide for New and Existing Buildings (2013, p28), which also contains a handy glossary. A detailed, ecological consideration of the movements of animals and plants within urban areas may be found in Richard Forman’s pioneering work Urban Ecology–Science of Cities (2014, Chapter 3).

47. Waste

In Chapter 4 of the seminal work Cradle to Cradle–Remaking the Way we Make Things (2009, pp92–117) Braungart and McDonough propose that the very concept of waste must be designed out of our industrial processes, and that by-products in one industry should be viewed as raw material for another, mimicking nature. Now often known as cradle-to-cradle solutions, it is this kind of thinking that is a primary message of Desai and Riddlestone’s Bioregional Solutions For Living on One Planet (2007). Chapter 1 (pp 15–23) sets out the issues and introduces some of the inspiring innovations that are later detailed within the book. The idea of waste as a resource is commonly described as a biomimetic principle (see Rule 52).

48. Ecosystems regulate climate

Climate on earth is physically regulated by ecosystems. The Biodiversity Information System for Europe (BIDE) states that climate regulation is one of the most important ecosystem services, since the terrestrial ecosystems–including deciduous forests, taiga (coniferous forest), grassland, desert and peatland–provide a carbon sink for up to 12% of European anthropogenic emissions. The relationship between carbon and global temperature control is neatly explained in an article by Holli Riebeek on Nasa’s excellent Earth Observatory website (earthobservatory.nasa.gov) titled The Carbon Cycle (2011). The Nasa site is a repository of many useful reports and articles, including one by Michael Carlowicz and Robert Simmon titled Seeing Forests for the Trees and the Carbon: Mapping the World’s Forests in Three Dimensions (2012), in which the authors confirm that forests globally store about 45% of all above-ground carbon. Pelsmakers, in The Environmental Design Pocketbook (2015, pp9–11), explains succinctly the mechanisms that link natural and anthropogenic carbon with climate change. The oceans also store CO₂, and in the article How Much CO₂ Can The Oceans Take Up? (2013) Robert Monroe, writing on the website of Scripps Institution of Oceanography, investigates the carbon uptake of the world’s oceans.

49. Climate-neutral buildings–carbon-storing materials

Half of the mass of timber is carbon, created by photosynthesis and stored within the tree. Berge, in The Ecology of Building Materials (2009, p35), urges us to maximise the amount of construction material of plant origin as a means of utilisng this natural carbon capture. In addition to massive timber elements, other plant-based materials and methods are discussed in detail (pp272–97), including:

• wood-derived products, such as wood-shaving insulation
• mosses and grasses
• straw bales
• peat
• cellulose

The chapter has a wealth of information on the characteristics and uses of materials, as well as options for such products as fire retardants and water-repellent additives. In continental Europe, construction systems such as Brettstapel, which uses low-grade timber to produce structural panels with no glue or nails, are becoming more common.

Other promising innovations in this field are described in the article Carbon Capture Pilot Turns CO₂ into Green Building Materials (August 2013) in the online journal Environmental Leader. In this case, the subject is the capture of carbon in bricks and paving slabs. ClimateTechWiki, in an article on the subject of carbon-sink materials discusses, in addition to timber:

• low-carbon bricks–using 40% fly ash
• ‘green’ concrete–replacing cement and aggregate with waste and recycled materials
• ‘green’ tiles–made using waste glass
• recycled metals
• bamboo

50. Building-reliant species

Gunnell et al, in Designing for Biodiversity: A Technical Guide for New and Existing Buildings (2013), provide an overview of the part that buildings play in biodiversity, and a detailed commentary on the needs and threats to building-reliant species. Contemporary technical solutions are given, as well as a wealth of references to further information. Pelsmakers, in The Environmental Design Pocketbook (2015, pp100–3), provides a detailed list of design recommendations for the highest-priority amphibians, birds, mammals and insects in the UK. Much international information on bats may be found at Bat Conservation International, and, in the UK, at the Bat Conservation Trust.

51. Density and nature

When the World Bank hosted a forum in 2012 based upon the idea of the ‘smart city’ (Smart Cities for All), comparing the US city of Atlanta (large, sprawling) with Barcelona in Spain (compact, dense) the result was an argument for high-density, small-footprint cities with a focus on transportation. The central message of Vishaan Chakrabarti’s strongly argued and well-illustrated proposition A Country of Cities (2013) is the need for urban density, and another urbanist, Stephen Wheeler, in his essential reader Planning for Sustainability (2013, pp137–43), while also pro-density, discusses the advantages and challenges of both over-dense and sprawling cities, and of urban infill sites. Wheeler states that an essential future sustainability goal will be that of preserving green space (p140). Desai and Riddlestone, in Bioregional Solutions For Living on One Planet (2007, p75), warn of the potential hazards of urban density, correctly referring to the large resource needs of cities, transportation issues, waste and pollution management. Baruch Givoni, in Climate Considerations in Building and Urban Design (1998, pp291), acknowledges that the effects of urban density are conflicting: benefits in transport and infrastructure are set against impediments to ventilation and reduced natural lighting. Liddell, in Eco-minimalism, cites the example of Berlin, where half the footprint of any new development is to be given over to biodiverse landscape (2013, p88). The social, economic and environmental benefits of introducing nature into cities are neatly summarised by Pelsmakers in The Environmental Design Pocketbook (2015, p87). Adams, in Eco-Urbanity (ed Radovic, 2009, pp40–2), gives us a useful summary of the reasons density is essential, including:

• Reduced agricultural land loss
• Reduced travel distances and promotion of public transport
• Optimisation of costly infrastructure (roads, utilities)
• Reduced energy consumption

52. Lessons from nature and biomimicry

Petra Gruber, in the highly absorbing and detailed Biomimetics in Architecture–Architecture of Life and Buildings (2011, pp13–17), defines the subject and provides a helpful set of explanations of the terms used in relation to the science and art of seeking inspiration from nature and applying that inspiration to architecture. The author explains the relationships between nature and technology through the theory and practice of biomimicry (or biomimetics). Michael Pawlyn, in his take on the subject in Biomimicry in Architecture (2011), examines many inspirational examples of natural processes, structures and forms. Edwards, in an excellent essay in the Rough Guide to Sustainability (2014, pp185–91), discusses our distancing from nature, and the lessons we might learn by using nature’s successful models as a basis for good design.

53. The world’s climate zones

Robert Henson, in the Rough Guide to Weather (2007, pp43–7), gives an overview of the history of climate-zone definition and an easy-to-understand explanation of the mechanics of climate. Hocine Bougdah and Stephen Sharples, in their textbook Environment, Technology and Sustainability (2010, pp14 and 15), provide a useful, succinct description of the conditions to be found in each of the commonly described climate regions. Givoni, in the in-depth scientific work Climate Considerations in Building and Urban Design (1998, pp333–441), adds a fifth climate (cold-winter/hot-summer) to the usual four, and the required responses are described. Detailed strategies relating to climatic factors may be found in Brown and DeKay’s superbly illustrated Sun, Wind and Light: Architectural Design Strategies (2001). Studies in climate responsiveness can be made using many of the common software packages, and Climate Consultant 5, a tool developed by the University of California, Los Angeles (UCLA) into which global weather-data files are input, is intuitive and provides graphical architectural responses.

Factors to examine, as a minimum, in a preliminary study of the climate of a region include:

• sunshine and daylight hours
• diurnal and seasonal temperature range
• precipitation (rain and snow)
• humidity
• winds (direction and speed, diurnal and seasonal)
• beneficial vegetation

54. Learn from vernacular responses

Williams, in Sustainable Design (2007, Chapter 5), reminds us that historically communities naturally responded to their local environment in order to create conditions in which to thrive. Reference is made to many relevant vernacular precedents while explaining a very useful method of site analysis for climatic response to site. Wheeler, in Planning for Sustainability (2013, p32), is another of those in favour of approaches that learn from indigenous populations. The author points out that there are those who see such approaches as merely romantic. However, in Lessons from Vernacular Architecture: Achieving Climatic Buildings by Studying the Past (2014) the editors Willi Weber and Simos Yannas bring together a series of recent case studies that set out to prove that vernacular responses can still provide inspiration for innovation today.

Bokalders and Block, in The Whole Building Handbook (2010, pp665–8), touch on the history of traditional and regional responses, particularly in cold climates. The authors refer to Bernard Rudofsky’s Architecture Without Architects: A Short Introduction to Non-Pedigreed Architecture (1981), which remains a classic in the field. Van Lengen’s wonderfully illustrated The Barefoot Architect (2008), which focuses on the southern hemisphere, contains many examples of traditional techniques and applications.

55. The atmosphere and the weather layer

Nasa’s Jet Propulsion Laboratory at the California Institute of Technology tells us that the exosphere, the outermost layer of earth’s atmosphere, extends to 100,000km, but the Kármán line, at 100km from the earth’s surface, is usually used to denote the boundary between the atmosphere and space. Almost all the earth’s weather exists within the troposphere, which ranges between 7km at the poles and 17–18km at the equator. The ozone layer exists within the stratosphere, the upper boundary of which is the stratopause, at about 50km altitude. The Rough Guide to Weather (2007), by Henson, contains further information on the nature of the atmosphere and its relationship to weather, as well discussion on anthropogenic damage caused to the ozone layer. The links between the atmosphere and climate change are concisely described (pp150–68). The author also explains the impact of CFCs (chlorofluorocarbons) on the ozone layer (pp165–7). Gething and Puckett, in Designing for Climate Change (2013), succinctly introduce the relationship between CO₂ and climate change; the scenarios for future climate; and then, through a series of contemporary case studies, they identify various design mitigation approaches.

56, 57 and 58. Urban climatology and the Urban Heat Island (UHI)

In hot regions, health and wellbeing may be particularly affected by elevated night-time temperatures (caused by both stored solar energy and human-generated heat) and their detrimental effect on sleep patterns. Conversely, UHI is usually beneficial in winter and in cold climates. UHI may therefore be a positive or a negative influence depending on the climate region and season. Bokalders and Block, in The Whole Building Handbook (2010, p544), writing about cities in cold climates, state that the urban temperature in winter might be 5–10ºC higher than the surrounding countryside. Haggard et al also provide some facts and figures in the Passive Solar Architecture Pocket Reference (2009, p18): urbanisation, they tell us, leads to reduced heating loads, increased winter temperatures (by 1–2ºC), reduced solar radiation (by 15–20%), increased precipitation (5–10%) and increased cloud cover (5–10%). Mechanical air conditioning (for cooling in hot cities) is specifically cited as a major influence on UHI, by these and other authors; the urban heat island effect increases the need for air conditioning, which in turn amplifies the effects of UHI. Urban climatology and UHI are very well explained by Givoni in Climate Considerations in Building and Urban Design (1998, pp241–4), and Givoni reminds us that UHI is essentially a nocturnal phenomenon, with the greatest effect being felt on clear, still nights. Givoni identifies the key contributors to UHI:

• The lower rate of nocturnal radiant cooling compared with the surrounding countryside
• The release at night of solar energy stored in the mass of the city and its buildings in daytime
• Lower evaporation in the city (reducing the effects of evaporative cooling)
• Anthropogenic heat generation in cities (transport, industry)
• Seasonal heat sources, such as heating and air conditioning, which release energy into the urban air dome

The broader effects of urban climate and UHI are discussed further by Ritchie in Sustainable Urban Design (2009, p6). Ritchie reminds us about increased air pollution, pressure on drainage systems and the difficulties of achieving natural cooling on hot summer nights. In Chapter 4 of the same text the positive influence of urban landscape on the city’s microclimate is addressed by Von Borcke in Sustainable Urban Design (eds Ritchie and Thomas, 2009, pp31–3). A more detailed explanation of the link between cities and climate change is given by Edwards in the Rough Guide to Sustainability (2014, pp9–13), and here the author states that increased global CO₂ production is a direct result of urbanisation.

Although most research has been focused on temperate climate regions and cities with an agricultural hinterland, thus restricting our knowledge, Givoni, in Climate Considerations in Building and Urban Design (1998, pp245 and 246), sets out aspects of urban temperature elevation that humans can control:

• Colour (the albedo effect–see Rule 66)
• Vegetation, which can reduce urban temperatures
• Energy used for heating and air conditioning
• Heat loss from the building fabric, which is greatly influenced by thermal performance
• Density of the urban fabric, affecting the amount of solar radiation reaching the ground
• Orientation of streets in relation to wind, influencing wind speed

59. Climate clues for city planning

Bokalders and Block, in The Whole Building Handbook (2010, Section 4.1.4), state that temperature is influenced by topography, proximity to coast and building density, and that the temperature-moderating influence of a large body of water will be a few degrees (p543). The authors also propose siting buildings in the warmest locations in cold climate regions, such as where snow first melts in spring. Givoni, in Climate Considerations in Building and Urban Design (1998, pp267–80), provides further detail, discussing the effects of topography on wind and rainfall and stating that the temperature-moderating effect of large water bodies, such as oceans and large lakes, reaches 20km inland. Givoni states that controlling wind conditions offers the greatest potential of all interventions for modifying the urban climate and influencing both human comfort and energy consumption (pp256–66).

Beer and Higgins, in Environmental Site Planning for Site Development (2000, pp66–91), give an excellent synopsis of climate and microclimate factors in sustainable site planning, including what information the designer needs to gather.

Back at the global scale, in the highly readable, utopian viewpoint found in Richard Register’s EcoCities: Rebuilding Cities in Balance with Nature (2006, Chapter 11), we find illustrations of imagined cities in three global climate regions, indicating their responses to sun, wind and daylight.

60. Building separation for sun, light, wind and energy

Rules of thumb for separation are some of the most difficult to extract as they are latitude dependent. Also, there is no universal definition of the boundaries of the high, mid and low latitudes. Paul Littlefair, in Passive Solar Urban Design: Ensuring the Penetration of Solar Energy into the City (1998), is one of the few researchers who attempts to define separations using solar elevations (degrees of the sun above the horizon) based on high, mid and low latitude bands. In the current book, the bands are explained using the following widely accepted definitions:

• High latitude = 60° magnetic latitude and higher
• Mid latitude = between 50° and 60° latitude
• Low latitude = below 50°

Other authors define separation by relating building heights to distances apart. Both methods may be useful as a starting point for designers, so this author provides rules of thumb for both degrees and distances. The designer should use the most advantageous method in the early design stages, remembering that urban place-making and other environmental matters (eg protection from wind) should not be overlooked.

Brown and DeKay, in Sun, Wind and Light: Architectural Design Strategies (2001, p119), provide a table that allows the designer to deduce appropriate distances between parallel building blocks for solar access and solar gain at various latitudes. There are diagrams showing the shading effects of different spatial configurations and street orientations (p129). The overall climatic impacts of street widths and orientations in different climate regions are explained by Givoni in Climate Considerations in Building and Urban Design (1998, pp286–90). Bokalders and Block, in The Whole Building Handbook (2010, Section 4.1.4), give a useful proposal for residential development in Scandinavia (p538) indicating which spaces need how much sunlight, and when. Based on the equinoxes, the designer is urged to provide:

• for kitchens and living rooms: 4 hours
• for outdoor balconies: 4hrs after 12.00 midday
• for open recreation areas within 50m of building entrances: 5 hours between 9.00 and 17.00

61. Urban breaks for solar access

In some cases, the spacings discussed in Rule 60 are unachievable–but there are remedies for the effects of urban density, and Pelsmakers, in The Environmental Design Pocketbook (2015, p79), gives a detailed set of recommendations for ‘urban break’ design. The author also points out that increased complexity of form generates additional surface area, which needs to be offset with increased fabric insulation. Ritchie and Thomas, in Sustainable Urban Design (2009, pp46–9), discuss density, spacings and form in relation to energy use–in doing so, reminding us that the simple act of placing taller buildings to the north of a site (or south in the southern hemisphere) preserves solar access.

62. The building envelope as climate modifier

Givoni, in Climate Considerations in Building and Urban Design (1998, Chapters 10–13), provides an in-depth appraisal of the conditions in each of the earth’s five climate regions and the general performance requirements of the building envelope. Givoni’s work greatly influenced Chapter 5 of the first book in this series, 101 Rules of Thumb for Low-energy Architecture (2012), which explains and illustrates climatic envelope issues–including the glazing types to be considered; where high thermal mass will be beneficial; and the types and uses of openings and integrated elements, such as shading devices and wind catchers. Van Lengen, in The Barefoot Architect (2008), deals with simple, practical building-construction methods for hot-dry, humid and temperate regions in the southern hemisphere. He provides a wealth of finely illustrated detail about materials, structures, envelope and openings.

63. The section

Lorraine Farrelly, in Representational Techniques (2008, pp78–81), describes the section as one of the most useful drawings in architecture. It is a key design tool, without the use of which the designer will not be able to fully explore spatial possibilities. In addition to being the drawing that makes a connection between two-dimensional plans and three-dimensional volumes, and between outside and inside, the section is the format most used to explain the environmental and sustainable design aspects of a project. Francis Ching, in the seminal Architectural Graphics (2009, pp63–73), makes the distinction between the design section and the construction section, and also describes the site section: the drawing that illustrates the connection between a building and its environment.

64 and 65. Wind

Bokalders and Block, in The Whole Building Handbook (2010, pp539–42), provide a good explanation of the effects of, and solutions to, wind problems in both rural and urban situations. Brown and DeKay, in Sun, Wind and Light: Architectural Design Strategies (2001, pp99–101), deal with the wind effects generated by tall buildings. They provide detailed strategies (pp102–9) for urban wind control through variations in block and street patterns and in building heights. Matin Alaghmandan et al, in a paper titled Innovative Design Methods for Tall Buildings–a Computational-based Approach in Optimizing the Wind Effects on Tall Buildings (2013 p527), state that aerodynamic (ie non-rectilinear) forms reduce the formation of vortices around buildings; structural issues relevant to tall-building wind design are also discussed. Pelsmakers, in The Environmental Design Pocketbook (2015, pp72–5), explains the UK’s wind patterns and provides very clear explanatory diagrams for designing with wind. A detailed research study of the physics and impacts of wind around buildings may be found in a paper by Bert Blocken and Jan Carmeliet (2004), titled Pedestrian Wind Environment around Buildings: Literature Review and Practical Examples. The authors draw important conclusions for designers, including that:

• a poor wind environment around a building can lead to unsuccessful and hazardous development
• wind needs to be considered at the outset of a design, as its effects are very hard to mitigate after a building is complete

66. Green roof, blue roof or white roof?

67 and 68. Comfort, control and satisfaction

69. Maintenance and sustainability

Liddell, in Eco-minimalism (2013, p95), states, ‘If something is to be sustainable it must also be maintainable’, implying a relationship with longevity and usefulness. Bokalders and Block, in The Whole Building Handbook (2010, Section 1.3), consider the care and maintenance of buildings as a function of good design and construction. Ease of cleaning and the environmental credentials of cleaning materials are discussed, and we are reminded that building components must be accessible safely. The relationship between energy efficiency, user satisfaction, ease of maintenance and facilities management is made by Pelsmakers in The Environmental Design Pocketbook (2015, p349). There is an excellent maintenance checklist (pp30–1), and maintenance of materials is also covered (p210). Van Lengen, in The Barefoot Architect (2008), deals with humid tropical regions (Section 2), and maintenance of materials is the first consideration in the section on materials selection (p296). Sandy Halliday, in Sustainable Construction (2008, p132), warns us about claims of so-called maintenance-free construction, which is an impossible state to promise.

70 and 71. The benefits of contact with nature

Mark DeKay, in his highly readable and thought-provoking treatise Integral Sustainable Design (2011, pp354–424), states his view that we relate nature to a sense of place and that the cycles of nature provide meaning in our lives. He also reminds us that in a pre-industrial world we would have sought the right environmental conditions that existed at any particular time of day or season, in a particular place within our buildings. Edwards, in the Rough Guide to Sustainability (2014, pp185–91), reflects on the benefits of incorporating an explicit reading of nature into design, with examples of ways in which nature has been used as a source of inspiration to inform design in practical, material, tactile, visual and other less tangible ways. Von Borcke, in Sustainable Urban Design (eds Ritchie and Thomas, 2009, pp31–41), writes engagingly on nature in the city and explains how the colour green is linked with human biology and physiology. Urban greening and the benefits of urban landscape are discussed in relation to Rule 80. Very well-described case studies of approaches to nature may be found in Sassi’s Strategies for Sustainable Architecture (2006, pp32–43).

72. Healthy (and sick) buildings

Bokalders and Block, in The Whole Building Handbook (2010, pp1–4), begin with a description of the nature of healthy buildings and the causes of sick buildings. Edwards and Naboni, in Green Buildings Pay (2013, pp71–5), discuss occupant satisfaction and the relationship between health and productivity both in mechanically and naturally ventilated environments. The authors confirm (p69) that the cost of employing staff far outweighs the operational energy costs of an office building–so sick buildings, often associated with many attributes of unsustainable design, are extremely costly to operate. The Alliance for Sustainable Building Products (ASBP, reported in January 2014 that Google required a ‘declaration of content’ of all building products to be used in their new London offices, reminding us that toxicity is also a potential liability issue. Birkeland, in Positive Development (2008, pp28 and 29), provides examples of buildings and retrofits, illustrating the benefits of healthy buildings.

73. Indoor Air Quality (IAQ)

The United States Centers for Disease Control and Prevention has an excellent website wherein the document Factors Affecting Indoor Air Quality may be found. IAQ features in a practical ‘Internal Environment’ checklist in Pelsmakers’ The Environmental Design Pocketbook (2015, pp152 and 153). Good ventilation, and materials that do not emit noxious gases are cited as simple remedies. Edwards, in the Rough Guide to Sustainability (2014, pp232 and 233), discusses the dangers of Volatile Organic Compounds (VOCs), which can be 10 times higher inside buildings than outside. The US Environmental Protection Agency, which has a good web-based resource on its website, confirms that there are literally thousands of sources of VOCs in the indoor environment. Berge, in The Ecology of Building Materials (2009, Part 1, Section 2), provides a detailed review of pollution and pollutants in the construction industry. Some VOCs are highly toxic and carcinogenic, and the UK Government’s PostNote Number 366: UK Indoor Air Quality (November 2010) has a table of common pollutants, their sources and health impacts with recommendations. The unintended consequences of low-energy retrofit are discussed in relation to air quality in Chapter 5 of this narrative bibliography.

74. Seasonal Affective Disorder (SAD)

Although there is evidence that it can occur in summer too, the illness SAD–sometimes known as ‘winter depression’ or ‘winter blues’–is a medical condition brought about mainly by the reduced availability of daylight. In A Literature Review of the Effects of Light on Building Occupants (2002, pp8 and 9), L Edwards and P Torcellini discuss the medical conditions associated with SAD, which can include clinical depression lasting several months. The excellent daylighting textbook by Peter Tregenza and Michael Wilson, Daylighting–Architecture and Design (2011, pp6–9), provides further discussion on human physiological responses to daylight, and SAD is discussed in relation to interior lux levels. Although it is thought to be most prevalent in higher northern latitudes (and most of the research has been conducted in these regions), there is evidence that seasonal variations and sunshine hours are factors irrespective of latitude; research by Shrikant Srivastava and Mukul Sharma, Seasonal Affective Disorder: Report from India (1998), studied patients at latitude 26^o 45’ north and found evidence of the existence of SAD there.

75. Post Occupancy Evaluation (POE)

Clients should be appraised of the importance of the building performance evaluation, known as Post Occupancy Evaluation (POE). Bordass et al, in A Guide to Feedback and Post-occupancy Evaluation (2006), includes much practical advice and mentions the ‘soft landings’ approach, whereby the design team assists in the transition from building handover to operation. The UK Government’s Cabinet Office document Government Soft Landings (2013) details this approach and its relationship to BIM. The approach considers:

• Functionality and Effectiveness
• Environmental factors
• Cost factors

Note that these headings relate closely to the ‘Three Es’ of sustainability (see Rule 3). The purpose and methods of POE are very well described in the essay by Roderic Bunn, ‘From post-mortem to life support’ in the book Retrofit for Purpose (Ed Prasad, 2014, pp39–53) by the architectural firm Penoyre & Prasad. The author states, rightly, that POE is a process for the whole design team, including the client.

76. Preserving cultural heritage

Gaines and Jäger, in their forthright Manifesto for Sustainable Cities (2009, p20), confirm that in planning the future of existing cities the past must be taken into account, and Ritchie, in the introduction to Sustainable Urban Design (Eds Ritchie and Thomas, 2009, pp4–5), lauds the ‘happy accidents’ that occur in our cities when a layering of old and new results in an unplanned richness, linking the present to the past and contributing to social sustainability. Ritchie’s views concur with ideas proposed by Colin Rowe and Fred Koetter in their seminal critique of urbanism, Collage City (1978). Richard Rogers, in Cities for a Small Planet (1997, p82), states that preserving heritage is meaningless to society if innovation is lost. An excellent, concise paper by S Mutal for UN-Habitat, A World Overview on Conservation, Rehabilitation, Development and Management of Historic Cities/Centres (2004), describes how heritage must be part of the daily life of human beings in the city–and states that new and old can, and should, exist together. History, as the author reminds us, is all-encompassing and includes social and economic factors, urban ritual and physical landscape. This paper (and Rogers, in Cities for a Small Planet, too) quotes the historian Roy Porter: ‘when buildings take precedence over people, we get heritage, not history’. Rodwell, in Conservation and Sustainability in Historic Cities (2007), writes very well about the richness of fabric in an existing city (p114) and approaches to cultural heritage, with numerous case studies (Chapter 9).

77. An active city is a healthy city

Chakrabarti, in A Country of Cities (2013, pp75–123), gives compelling evidence for the need for mobility and the opportunities afforded by dense cities. Issues of health and activity are central to Danish architect and urban designer Jan Gehl, in the influential, very readable and well-illustrated work Cities for People (2010). Confirming many of Gehl’s thoughts, Johan Faskunger, in a research paper titled Promoting Active Living in Healthy Cities of Europe (2011) based on a World Health Organization (WHO)-sponsored city study, clearly sets out the problem of our sedentary modern lifestyles. The lack of a coordinated effort within the layers of city governance is cited as a common barrier to promoting active city living. In the Journal of Urban Health, Hugh Barton and Marcus Grant, in the paper Urban Planning for Healthy Cities: A Review of the Progress of the European Healthy Cities Programme (2011), provide their take on the determinants of the healthy city, as an antidote to the car-dependent and unhealthy lives encouraged by many cities today. They provide us with the 12 objectives of Healthy Urban Planning (HUP) as defined by the WHO, which make interesting reading as they touch on social, organisational and built-environment issues. Camilla Ween, in Future Cities–All That Matters (2014, p60), proposes a ‘feet first’ approach to public transport: citizens will walk if the opportunity exists and if the public realm is attractive. CJ Lim, in Food City (2014, p135), states that gardening is also an exercise regime recommended to beat urban obesity. The WHO’s Healthy Cities project, a global movement for urban health provides links to news, events and facts sheets within this WHO initiative.

78 and 79. Sound and noise

Authors Katherine Irvine et al, in ‘Green space, soundscape and urban sustainability: an interdisciplinary, empirical study’ (2009) in the International Journal of Justice and Sustainability, cite the almost total lack of natural sounds in a typical city-centre park and the increase in traffic noise in our cities. An interesting conclusion is that the soundscape (the totality of the sound experience) in urban parks is influenced directly by the variety of bird species. Canadian researchers Darren Proppe, Christopher Sturdy and Colleen Cassady St Clair, in Anthropogenic Noise Decreases Urban Songbird Diversity and may Contribute to Homogenization (2013), revealed that songbirds were retreating from noisy urban parks. The clear conclusion is that ecology needs to be reinforced in order to enhance the natural elements of the urban soundscape. A fascinating study by William Davies et al, Perception of soundscapes: An interdisciplinary approach (2013), distinguishes natural, human and mechanical sounds, and confirms that soundscape connects us with place and society. Sounds, and their part in defining the ecology of a landscape, are the subject of an online article from the Ecology Global Network by Cheryl Dybas of the National Science Foundation, titled Soundscape Ecology: Studying Nature’s Rhythms (2012). Soundscape is defined as being composed of the following:

• Biophony: the music created by organisms like frogs and birds
• Geophony: the composition of non-biological sounds like wind, rain and thunder
• Anthrophony: the conglomeration of noise from humans

Acceptable noise levels are a factor in HUP, as identified by Barton and Grant, in Urban Planning for Healthy Cities: A Review of the Progress of the European Healthy Cities Programme (2011). Ritchie and Thomas, in Sustainable Urban Design (2009, pp50 and 51), touch on two key acoustics issues: noise generated by external sources and noise transmission within buildings. Further information, and attenuation details, may be found in Environmental Design (2006, pp46–49) in which the author, Randall Thomas, sets out the difficulty of attenuating high levels of external noise. Pelsmakers, in The Environmental Design Pocketbook (2015, p95), provides detail on the means of reducing traffic noise with a vegetation buffer. However, the author cautions us that vegetation is unlikely to be effective on its own. Beer and Higgins, in Environmental Site Planning for Site Development (2000, p115), comment that people appear to be less disturbed by noise whose source they cannot see, so vegetation might have psychological benefits. The authors also point to the acoustic benefits of the rustling of trees in wind, and of the sound of water moving in the city, masking less pleasant sounds.

80. Greening the city

The benefits of urban greenery are discussed in detail, with useful checklists, by Pelsmakers in The Environmental Design Pocketbook (2015, Chapter 4). The ‘park cool island’ effect is explained, in which temperatures are reduced by 2–3ºC compared with surroundings. Urban green spaces provide beneficial cooling for a considerable distance: 150m or more into the urban fabric, according to Givoni in Climate Considerations in Building and Urban Design (1998, pp 308–10). The cooling potential of urban spaces is described in detail by Brown and Mark DeKay in Sun, Wind and Light: Architectural Design Strategies (2001, pp121–4). Von Borcke, in Sustainable Urban Design (Eds Ritchie and Thomas, 2009, pp31–4), identifies the ways in which nature and landscape in cities improve quality of life for inhabitants; these include ecological, social and consequential economic benefits, which even a small outdoor space can bring. Ian Alcock et al, in a paper titled ‘Longitudinal Effects on Mental Health of Moving to Greener and Less Green Urban Areas’ (2013) in the Journal of Environmental Science and Technology, confirm that mental health improves enduringly when people move to greener urban areas. Cliff Moughtin and Peter Shirley, in Urban Design–Green Dimensions (2005, p81), provide a useful typology of green spaces of various scales.

81. Mixed-use cities

A very good description of the benefits of what Wheeler terms ‘diverse urban form’ may be found in his primer, Planning for Sustainability (2013, p142). Diversity through mixed uses is a sustainability issue as it leads to a healthy and vibrant overlapping of different groups in society, with reduced car use and pollution and attractive and popular varieties of form and function. The sprawling modern metropolis is the opposite. The influential author and activist Jane Jacobs, in The Death and Life of Great American Cities (1961), advocated mixed uses to achieve vital diversity, and diversity is a compelling theme in Rogers’ Cities for a Small Planet (1997), in which the author argues passionately against separation and for the humanity manifest in ‘living neighbourhoods’ (p15). Rodwell, in Conservation and Sustainability in Historic Cities (2007, pp117–19), describes the ‘urban village’ concept of mixed-use development. A very clearly written document explaining the practical benefits of mixed-use cities is provided by Paul Beyer in Livable New York–Sustainable Communities for all Ages (2012, Section II.2.g).

82. Feeding the city

Jennifer Cockrall-King, in Food and the City–Urban Agriculture and the New Food Revolution (2012, pp78–80), considers the sensible idea of actually planning cities with food in mind. Small- and large-scale case studies illustrate the possibilities (such as the ‘edible landscaping policy’ in the city of Vancouver) and challenges. An excellent, and entertainingly written, global account of food supply and the status of sustainable urban agriculture (and the culture of food), with many examples of innovation and invention may be found in Lim’s Food City (2014). Ween writes about ‘the edible city’ and provides an optimistic account of urban agriculture, including a description of vertical farms, in Future Cities (2014, Chapter 6). The author opines that cities are capable of growing within their boundaries a significant proportion of the food that they consume (p 71). Birkeland, in Positive Development (2008, pp281 and 282), describes the multiple benefits of an applied ‘green scaffolding’ approach to retrofitting buildings. The allotment strategies for UK towns and cities such as Oxford, Darlington and Canterbury provide a very useful resource, including the history of allotments and travel distance data, and may be found on the relevant councils’ websites. Viljoen et al, in Continuous Productive Urban Landscapes: Designing Urban Agriculture for Sustainable Cities (2005), provide a fascinating and very well-illustrated proposition for connections between urban and extra-urban productive greenspace, defined as CPULs. A superbly written, must-read work, Hungry City (2013) by Carolyn Steel gives the reader a fascinating and inspirational account of the history and future of how the planet’s cities are fed. Forman, in Urban Ecology (2014, pp344–9), tells us that in the US (at year 2000) the average distance a piece of food travels to where it is eaten is 2,400km. There is an excellent description of the ecology of agriculture and the relationship between agriculture and the city.

83. Inclusivity

Robin Hambleton, in Leading the Inclusive City–Place-based Innovation for a Bounded Planet (2015), states that cities are becoming more, not less unequal–and that this threatens all citizens. The inclusive city–which results from a partnership between citizens, locally-based civic leadership and the environment–is defined (p6), and the author confirms that public transportation improvements are key to inclusivity as they have a transformative influence on lifestyle and opportunity (p314). The author emphasises how the time has come for city leadership to place equity over economic growth. The work uses case studies (‘innovation stories’) to illustrate key themes for successful, inclusive and sustainable cities.

Wheeler, in Planning for Sustainability (2013, Chapter 4), discusses how inclusivity is part of the notion of equity, and explains how varying wealth in urban areas leads to ‘social isolation’ or exclusion as the rich/poor divide grows. Urban equity is related to affordable social housing. Quoting urbanist Kevin Lynch, Wheeler interprets the importance of ‘accessible’ cities. Leading on from this, Birkeland, in the optimistic and wonderfully challenging text Positive Development (2008, Chapter 13), states that society can only be sustainable if everyone becomes ‘better off’. In the academic yet practical text by Susan Fainstein, The Just City (2010, Chapter 2), inclusivity is discussed in relation to diversity. We are, however, urged to be wary of the inauthenticity that can result from a planned forcing together of communities.

84 to 89. Strategies for sustainable retrofit

90 to 101. Strategies for sustainable architecture and cities