Sustainable Housing for Sustainable Cities

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SUSTAINABLEHOUSING fOrSUSTAINABLE

CITIESA POLICY FRAMEWORK FOR DEVELOPING COUNTRIES


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SUSTAINABLE HOUSING FOR SUSTAINABLE CITIES:A POLICY FRAMEWORK FOR DEVELOPING COUNTRIES

First published in Nairobi in 2012 by UN-Habitat.Copyright United Nations Human Settlements Programme 2012.All rights reserved.

United Nations Human Settlements Programme (UN-Habitat)P. O. Box 30030, 00100 Nairobi GPO KENYA.Tel: 254-020-7623120 (Central Oce).www.unhabitat.org

HS/073/12E

ISBN: 978-92-1-132488-4

Disclaimer:

The designations employed and the presentation o the material in this guide do notimply the expression o any opinion whatsoever on the part o Secretariat o the UnitedNations concerning the legal status o any country, territory, city or area o its authorities,or concerning the delimitation o its rontiers or boundaries. Views expressed in thispublication do not necessarily refect those o the United Nations Human SettlementsProgramme, the United Nations, or United Nations Member States.

Acknowledgements:

Principal authors: Oleg Golubchikov and Anna Badyina.

Supervisor: Christophe Lalande.

Task manager: Matthew French.

Design and layout: Emma-Liisa Hannula.

Editor: Matthew French.

Contributors: Claudio Acioly, Mohamed El-Siou, Emma-LiisaHannula, Channe Oguzhan

UN-Habitat also acknowledges the indviduals who contributed to the development othis publication during an Expert Group Meeting held in Nairobi, Kenya in December

2011: Carmen Antuna, Maike Christiansen, Skye Dobson, Oliver Frith, PhilippeGarnier, Curt Garrigan, Pekka Huovila, Daniel Irurah, Michelle Malanca, MartinMulenga, Maria Nystrm, Michael Ramage, Kurt Rhyner, David Sanderson, ClaudiaSchneider, Martin Suvatne, Diana Urge-Vorsatz, Pauline Wangui, Said Yahya.

Programme support: Helen Musoke and Christina Power.

Cover photo: Urban view in Istanbul, Turkey Matthew French/UN-Habitat.

Printing: UNON, Publishing Services Section, Nairobi, ISO14001:2004-certied


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SUSTAINABLE

HOUSING fOrSUSTAINABLE

CITIESA POLICY FRAMEWORK FOR DEVELOPING COUNTRIES


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Table of ConTenTs

EXECUTIVE SUMMARY 1

CHAPTER 1 HOUSING AND SUSTAINABILITY 3

1.1. What is sustainable housing? 3

1.2. The purpose and structure o the Guide 4

1.3. Housing challenges in developing countries 5

1.4. Why sustainable housing? 6

CHAPTER 2 ENVIRONMENTAL SUSTAINABILITY OF HOUSING 13

2.1. Consider the whole liecycle o residential buildings 14

2.2. Urban orms and residential densities 14

2.3. Mitigate environmental hazards and improve green spaces 16

2.4. Environmental perormance o residential buildings 162.5. Sustainable building material and practices 24

2.6. Integrate housing into sustainable community inrastructure 27

CHAPTER 3 SOCIAL AND CULTURAL SUSTAINABILITY OF HOUSING 33

3.1. Aordability, dignity and resilience o housing 33

3.2. Social and spatial justice 36

3.3. Empowerment, participation and inclusion 39

3.4. Social inrastructure and acilities 39

3.5. Residence as coping strategies 40

3.6. Adaptable housing or present and uture needs 43

CHAPTER 4 ECONOMIC SUSTAINABILITY OF HOUSING 46

4.1. Aordability o housing supply 48

4.2. Balanced housing markets and the choice o aordable tenure 48

4.3. Sustainable aordable house-building as a source o employment 49

4.4. Recognise home based enterprises 52

4.5. Mobilize savings and domestic nance 53

CHAPTER 5 DELIVERING HOLISTIC APPROACHES 58

5.1. Find a balance across the sustainability dimensions 58

5.2. Use the instrument o spatial planning more eectively 59

5.3. In-build resilience in housing development 62

5.4. Mainstream best practices 63

CHAPTER 6 KEY PRINCIPLES FOR SUSTAINABLE POLICY DELIVERY 66

REFERENCES 69

SUSTAINABLE HOUSING FOR SUSTAINABLE CITIES: A POLICY FRAMEWORK FOR DEVELOPING COUNTRIESiv |


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lIsT of boXes

Box 1: Sustainable development 4

Box 2: Climate change, mitigation and adaptation 7

Box 3: Sustainable houses 9

Box 4: Increasing housing demand in our urban uture 10

Box 5: Multiple benets o sustainable housing 11

BOX 6: THE REHABILITATION OF AL-AZHAR PARK IN CAIRO, EGYPT 17

Box 7: Green roos 19

Box 8: Low carbon cities 21

Box 9: Preabricated buildings 24

Box 10: Should zero-energy be a target or sustainable housing policy? 26

Box 11: Environmental assessment and international rating systems or buildings 29

Box 12: A culturally-aware use o low-cost building techniques 30

Box 13: Experiences o biogas generation rom landlls and human waste 31

Box 14: Mexicos strategy or sustainable aordable housing 34

Box 15: Cultural dimensions in aordable housing programmes in Ethiopia 42

Box 16: Housing adaptation and repair scheme in Malta 44

Box 17: Remaking traditional building design or fexible housing 44

Box 18: tHE Importance o aordable housing activities or economic development 47

Box 19: Brazils Aordable Housing Programme - My House, My Lie 50

Box 20: Employment in home-based enterprises in selected countries 53

Box 21: Alternative housing nance schemes 55Box 22: Community-based housing loans 55

Box 23: Contribution o planning to sustainable aordable housing 61

Box 24: National housing strategy or sustainable housing 68

lIsT of fIGURes

FIGURE 1: SHORTCOMING OF THE PRESENT HOUSING POLICY RESPONSES. 9

FIGURE 2: WINDOW OVERHANGS: USING PASSIVE LIGHTING AND ACTIVE SHADING. 19

FIGURE 3: A CONCEPTUAL REPRESENTATION OF THE SOCIAL SUSTAINABILITY OF HOUSING. 36

FIGURE 4: PROVISION OF AFFORDABLE HOUSING OPTIONS FROM THE POLICY PERSPECTIVE. 51FIGURE 5: TOP-DOWN AND BOTTOM-UP ROUTES TO SUSTAINABLE DEVELOPMENT. 64

FIGURE 6: SUSTAINABLE HOUSING POLICY. 67

lIsT of Tables

TABLE 1: A MULTI-SCALE FRAMEWORK FOR SUSTAINABLE HOUSING POLICIES. 8

TABLE 2: GUIDING MATRIX FOR ASSESSMENT OF ENVIRONMENTAL SUSTAINABILITY. 15

TABLE 3: MINIMUM STANDARDS FOR HOUSEHOLD ENERGY SERVICES TO SUPPORT DECENT WELLBEING. 21

TABLE 4: SUPPORTING COMMUNITY SOCIALISATION. 38

TABLE 5: HOUSING TENURE STRUCTURE IN SELECTED COUNTRIES AND CITIES. 51

TABLE 6: EMPLOYMENT GENERATED BY DIFFERENT CONSTRUCTION TYPES IN SRI LANKA 54

TABLE 7: EXAMPLES OF CROSS-DIMENSIONAL SUSTAINABILITY CONSIDERATIONS. 59

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Planned urban expansion in Morocco. Matthew French/UN-Habitat.


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EXECUTIVE SUMMARY

eXeCUTIVe sUMMaRY

In a rapidly changing and urbanising world, theprovision o adequate and aordable housingremains a key priority or all governments.However, the concept o housing requires a newunderstanding to eectively and synergistically

address the pressing issues o slums prevention,the urban divide, economic and humandevelopment, and climate change. No longerregarded as simply a roo over ones head,housing today plays a crucial role in achievingsustainable development as envisaged by theidea o sustainable housing.

Sustainable housing is, however, yet to gain itsdue prominence in developing countries. It is

rare that the social, cultural, environmental andeconomic acets o housing are addressed therein an integrated policy. In many developingcontexts, the so-called pro-poor housingprogrammes oten provide accommodationo poor standards, in remote locations, withlittle consideration to the residents liestyleand livelihood strategies. In others, rapidhousing developments create amplied carbonootprint and urther negative impacts on theenvironment. Yet in most developing cities,

decent and sae housing remains a dreamor the majority o the population, whilegovernment considers aordable housing asmerely a social burden.

Sustainable Housing for Sustainable Citiesoutlines key concepts and considerationsunderpinning the idea o sustainable housing

and provides a comprehensive ramework ordesigning sustainable housing policies andpractical actions. Although sustainable housingis oten considered rom a predominantlygreen perspective (resource saving, greenhouse

gas reduction), this report advocates a moreholistic approach, which recognises the multipleunctions o housing as both a physical andsocial system and which seeks to enhanceand harmonise the environmental, social,cultural, and economic dimensions o housingsustainability. Tus, along with the solutionsor the built environment (resource and energyeciency, environmental, ecological andhealth saety, resilience to natural disasters),

sustainable housing policies should deal withthe aordability, social justice, cultural andeconomic impacts o housing, and contributeto making healthy residential neighbourhoodsand sustainable cities.

It is only through sustainable solutions thatthe tensions between urban growth, climatechange, poverty alleviation, aordable housingprovision, and access to quality residentialservices, clean energy and environmental

conditions can be mitigated, while thepotential o housing or improved economicprosperity and social development can beurther unlocked. Well-designed, inclusive andparticipatory housing policies and programmeshave much to oer to this end.

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Planned urban expansion in Marocco. Matthew, French, UN-Habitat.

Sel-built housing using locally available materials in the Democratic Republic o Congo. Matthew French/UN-Habitat.


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CHAPTER 1 HOUSING AND SUSTAINABILITY

01HoUsInG anD sUsTaInabIlITY

1.1. WHaT Is sUsTaInableHoUsInG?

Housing is one o those basic social conditionsthat determine the quality o lie and welare o

people and places. Where homes are located,how well designed and built, and how wellthey are weaved into the environmental, social,cultural and economic abric o communitiesare actors that, in a very real way, inuencethe daily lives o people, their health, securityand wellbeing, and which, given the long lieo dwellings as physical structures, aect boththe present and uture generations. Housingis thereore central to sustainable development

(Box 1).

Housing is also part o the relationshipsbetween society and the environment. On theone hand, housing construction and operationconsume large amounts o natural resources(land, energy, water, building materials), whileproducing waste, air and water pollution. Onthe other hand, housing itsel is exposed to avariety o environmental impacts and hazards,including those associated with natural

disasters and climate change(see Box 2). Teseaspects are also signicant considerations orsustainable development.

Tis complex web o inter-relationshipsbetween sustainability and housing is addressedby the policies or sustainable housing. Tesepolicies consider a spectrum o underlyingconditions to achieve sustainability in housingdevelopment (along the our dimensions

o sustainability environmental, social,cultural and economic), such as: impactson the environment and climate change;

durability and resilience o homes; economicactivities in housing and their links with the

wider economy; cultural and social abrico communities and impacts o housing onpoverty alleviation, social development, and

the quality o lie.

Although sustainable housing is oten associatedwith wealth and afuence, it does not need to beso genuinely sustainable houses are those thatare inclusive and aordable or all. Addressingthe issue o aordability is, thereore, anecessary condition or transormation towardssustainable housing. And yet aordability isnot enough, because the so-called aordable

homes cannot be considered sustainable i theycreate negative impacts on the environment orsocial lie. Te marriage o aordability withother sustainability conditions is a must. Inthis Guide, the link between sustainability andaordability is discussed in the unied notiono sustainable housing.

Furthermore, while sustainable housing isoten considered rom a resource-saving(green) perspective, this Guide advocates a

more comprehensive approach viewingsustainable housing not simply as units orclusters o sel-sucient green buildings, butas socially-enhancing and environmentally-riendly residential practices integrated intothe wider urban/settlement systems. Tisapproach is necessitated by the holisticperspective o sustainable development andby the very multi-aceted nature o housing.Sustainable aordable housing in this regard

may be considered as extension o the adequate-shelter-or-all strategy o the Habitat Agenda(paragraph 60): Adequate shelter means

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Box 1: SuStaINaBlE dEvElopmENt

Sustainable development is a recognised principle or economic and social activities.Although it remains a shiting concept depending upon in which sustainability contextit is applied and rom which value position, a common ground understanding owes to the1987 Brundtland report (WCED, 1987) and the 1992 Rio Earth Summit, which denedit as meeting the needs o the present generation without compromising the abilityo uture generations to meet their own needs. Sustainable development is seen as amultidimensional process that links environmental protection with economically, sociallyand culturally sound development. Those links are reerred to as a our-dimensionalapproach to sustainable development, highlighting the need or a harmonious association

between environmental, economic, social and cultural dimensions.

more than a roo overones head. It also meansadequate privacy; adequate space; physicalaccessibility; adequate security; security otenure; structural stability and reliability;adequate lighting, heating and ventilation;adequate basic inrastructure, such as water-supply, sanitation and waste-managementacilities; suitable environmental qualityand health-related actors; and adequate andaccessible location with regard to work andbasic acilities: all o which should be availableat an aordable cost.

Box 3 gives a glimpse on the attributes thatsustainable homes may have, while able 1

provides a more comprehensive ramework orsustainable housing policies, which is organisedalong the our dimensions o sustainabledevelopment (environmental, social, cultural,and economic) and dierent spatial scales(rom national to household).

What is the meaning ofhousing in this Guie?

Te two interrelated unctions o housingneed to be acknowledged:

Housing as physical structure residential buildings/shelters, theirdesign, material qualities, theirarrangement in space, andtheir ecological interactions with the

physical environment;

Housing as social structure residence-based activities, their character, socialqualities, and their socio-economicinteractions in space with the immediatecommunities and wider society.

Trough both o these unctions, housingrepresents a system o social and materialrelationships, which is simultaneouslyarranged at the dierent spatial scales (homes,surrounding neighbourhoods, settlements,regions, countries) and which, thereore,requires a corresponding hierarchy o policy

interventions.

1.2. THe pURpose anDsTRUCTURe of THeGUIDe

It is the ramework summarised in able 1that shapes the discussions o this Guide. Tepurpose is to provide a detailed introduction

regarding the key aspects and concepts ordesigning and implementing sustainablehousing. Tis Guile will hopeully buildcapacity and can serve as an advocacy tool orcommunicating the importance o housingas a system within the urban system and,consequently, the importance o sustainablehousing or developing sustainable cities. Te

SUSTAINABLE HOUSING FOR SUSTAINABLE CITIES: A POLICY FRAMEWORK FOR DEVELOPING COUNTRIES4 |


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Guide should assist the national and local leveldecision makers, as well as other practitionersand proessionals o the housing sector,architects, international and development co-operation agencies, NGOs and CBOs andother stakeholders in their eorts to supportthe provision o sustainable aordable housing.

Tis Guide is structured as ollows. Te resto Chapter 1 will consider some main housingchallenges o developing countries and willprovide a urther case or sustainable housing.Te ollowing chapters will highlight thekey issues to consider or housing within theour-dimensional sustainability model that

is, environmental (Chapter 2), social andcultural (Chapter 3), and economic (Chapter4) dimensions, as ollows rom the rameworkpresented in able 1. It is important to stressthat the division into these dimensions issomething articial and should be understood asassistance with systematising and emphasisingdierent aspects o policies, rather than as adivision between policies themselves. Indeed,as sustainability emerges rom the overlaps and

synergies between the our dimensions, therewill be much overlap between the materialscovered under the dierent sustainabilityrubrics in the rest o this Guide. Tat will beurther stressed in Chapter 5 that considershow to balance the sustainability dimensionsin relation to housing policy and deliverholistic approaches. Te concluding Chapter6 highlights the key principles important orsustainable policy delivery.

1.3. HoUsInG CHallenGes InDeVelopInG CoUnTRIes

While the challenge to provide sustainableaordable housing is common or all countries,the need or decent aordable housing isparticularly acute in developing regions.Tese are experiencing rapid and continuingurbanization, driven by population growth

and migrations rom rural to urban areas (Box4). Urbanization increases the demand oraordable housing and urban inrastructure

and services, which cities struggle to copewith. As a result, urban growth in Asia, Aricaand Latin America is associated with slums andinormal settlements; shelters are built withlittle to no basic inrastructure and sanitaryprovision, and with negligible regard o ormalplanning and building regulations.

Wh are slums a challengefor sustainabilit?

Although slums and inormal urban areasprovide a crucial mechanism or the dwellingo many o the urban poor and disadvantaged,they pose a range o serious humanitarian and

environmental problems or both present anduture generations, including:

Environmental deterioration andlie-threatening problems related tosanitation and pollution (includingair and water pollution rom garbageand sewers);

Exposure to environmental hazards

(landslides, ooding, poor drainage);

Further health risks, diseasesand injuries related topoor construction, overcrowding,anti-social behaviour and crime;

Uncontrolled and conictual urbansprawls;

Inormal and extralegal economies;

Illegal and harmul inrastructuralconnections.

Tese problems, although not limited to slumareas, urther aggravate the vulnerabilities othe already deprived living conditions in thesame cities and their surroundings. Moreover,slums, squatter settlements, and other low-income houses oten occupy risk-prone areas

that are vacant and available to establishmakeshit residences. For example, i locatedin hilly and mountainous areas, many o

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them are exposed to landslides, which occursuddenly and can kill hundreds o residents(like in Rio-de-Janeiro State in Brazil in2010). In India and in many cities in Arica,such as Accra, Kampala, Lagos, Maputo, andNairobi, slums are also commonly ood-prone(Satterthwaite, 2007). Tese conditions willonly be exacerbated by the increasing climaticuctuations.

Tere are also challenges related to the accesso clean energy provision. oday, 1.3 billionpeople still do not have access to electricity most o these live in sub-Saharan Aricaand developing Asia. More than hal o the

population o the developing world depend onpolluting solid uels or cooking traditionalbiomass (1.7 billion people) or coal (0.4 billionpeople) (IEA, 2011). Indoor air pollutionrom solid uel use has been responsible oralmost 2 million deaths each year worldwideand causing other chronic illnesses, makingthis risk actor the most dangerous killer atermalnutrition, HIV/AIDS and lack o sae waterand sanitation. Tis disproportionably aects

the poorer amilies and especially childrenand women, who spend more time within thedomestic environment (WHO, 2011).

Even where governments succeed in tacklingthe challenge o slums and energy access, thereremain challenges o planetary importanceemerging rom the sheer volume o housing thathas to be built or renovated to accommodatenew population and address existing housingshortages and inadequacies. In China alone,

as much new building oor space is expectedto be built by the end o the next decade asthe entire existing building stock o the UStoday (UN-Habitat, 2011d). I the new-builthousing stock is not built with the utmostattention to sustainability and eciency(in all senses o these words), it will quicklyaccumulate a considerable new burden orthe environment and the climate, while alsomultiplying economic wasteulness and social

deciencies (c. Box 14 later in this Guide ora Mexican case). Furthermore, every time amajor renovation o a home is done without

due considerations to sustainability principles,another chance is missed or many years to reduceits environment ootprint. How many suchchances are being missed on the everyday basis?

Given that many developing regions havebeen successul in slowing down the growtho slums over the last decade or so (Box 4)and that much knowledge and capacity havealready been accumulated to this end, there isan increasing awareness that housing policiesmust shit towards bridging the aordable andsustainable agendas. Even in the regions whereconditions and resources are more challengingor tackling the slums and up-scaling sustainable

housing, like in Sub-Saharan Arica, there is aneed to change the conception o housing toembrace all o the sustainability dimensionsor designing more eective and sustainablehousing responses.

It is only through sustainable solutions thatthe tensions between economic development,social welare and equality, urban growth,housing provision, access to clean energy, good

quality residential services, and environmentalconditions can be alleviated.

1.4. WHY sUsTaInableHoUsInG?

Sustainable housing oers a great spectrumo opportunities to promote economicdevelopment, environmental stewardship,quality o lie and social equality, whilemitigating the precarious convergences o

the problems related to population growth,urbanisation, slums, poverty, climate change,lack o access to sustainable energy, andeconomic uncertainty.

It is seldom, especially in developing countries,that the social, cultural, environmental, andeconomic acets o housing are addressed inan integrated ashion. For example, aordablehousing is commonly considered on a cost

basis, while environmental and social issues(including people preerences, liestyles, andcultural aspirations), as well as economic



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impacts are thought to be addressed separatelyor totally ignored. However, ignoring one oranother dimension o sustainability only leadsto the accumulation o vulnerabilities andprecarious housing situations.

Tere is, or example, a large gap betweenpolicies or normal housing and aordablehousing these oten co-exist in parallel

worlds. Te so-called pro-poor, slumupgrading, and reugees housing programmesoten provide accommodation o standardsor in locations where people would live onlybecause o despair and necessity. Standardisedhouses are built in large-quantity matchbox

developments, cheaply, isolated rommainstream urban employment and servicesand do not cater or households varied needsand values. Saving on construction costs otenmeans substandard materials and techniques(rather than search or sustainable aordablealternatives) that render the dwellings short-lived and, urthermore, cause health problems(a sick house syndrome). Moreover, theseinitiatives do not provide a duly consideration

to energy and water eciency, leading tohouseholds being locked in wasteul practicesand unaordable running costs. Segregationo unemployment and poverty may only bereproduced in such locations rather thanresolved (Figure 1).

Planned and built within an integratedsustainability ramework, housing will not onlybe more accessible to low-income households,but will also respond to their diverse social andcultural needs and will have multiple positiveoutcomes or peoples physical and mentalhealth and saety, or economy, and or the builtand natural environments. Besides, sustainable

houses hold up or a longer time, making thema smart investment or government and otherstakeholders (see Box 5).

Te ollowing chapters will highlight thekey issues to consider or aordable housing

within the our-dimensional sustainabilitymodel according to able 1.


Box 2: ClImatE CHaNgE, mItIgatIoN aNd adaptatIoN

Climate change reers to the rise in the global average atmosphere temperatures, ollowedby an increased requency o climatic abnormalities, intensied heat and cold waves,droughts, storms, foods, as well as rising ocean level. The accelerated climate change isbelieved to be a result o human activities that increase the concentration o greenhousegases (GHG) in the atmosphere to which carbon dioxide (CO2) is the largest contributor.CO2 is naturally stored on Earth in carbon sinks such as ossil uels (oil, gas, coal, etc)

and green biomass. Human activities release this CO2 by the burning o ossil uels orenergy and the reduction o orests, grassland and peatland. Key mechanisms to limitGHG emissions (and thus to slowdown climate change) include switching to low-carbonenergies, reducing energy demands and preventing deorestation; these measures areknown as mitigation. However, adaptation measures to the already inevitable adverseimpacts o climate change are also needed.

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TABLE 1: A MULTI-SCALE FRAMEWORK FOR SUSTAINABLE HOUSING POLICIES.

MACRO (NATIONAL)

Environmentaldimension

Socialdimension

Culturaldimension

Economicdimension

MESO (REGION, CITY) MICRO (NEIGHBORHOOD, HOUSEHOLD)

Housing to support climatemitigation and adaptation eorts.

Mainstreaming green housingpractices and innovations.

Ensuring energy and resourceeciency in the building industry.

Integrating national housing andenergy systems.

Fullling the right to adequatehousing and promoting the right tothe city.

Ensuring aordable, decent andsuitable homes or all, includingdisadvantaged groups.

Developing social housing provision.

Promoting choice and security otenure.

Promoting links between housingand knowledge-based and culturaleconomies.

Promoting traditional, indigenousand local knowledge (including orelevance to sustainable resourceuse, energy eciency and resilientbuilding techniques).

Protecting cultural heritage.

Institutional capacities orsustainable housing markets andhousing development.

Articulating housing productivitywithin national economic systems.

Improving housing supply andeective demand, stabilising housingmarkets.

Improving housing nance options.

Promoting innovations in housing.

Stimulating necessary technologicaldevelopments or sustainablehousing.

Achieving good location and densityor residental areas and access toinrastructure.

Serviced land in environmentally sae

locations and green areas.Protection o ecosystems andbiodiversity.

Promoting sustainable and low-corbon urban inrastructure, publictransport and non-motorisedmobility, energy systems.

Waste management and recycling.

Promoting integrated comunitiesand ensuring trust in communities.

Providing community acilities,preventing segregation anddisplacement.

Regenerating and reintegratingneglected areas into regional,urban abric.

Ensuring inrastructural integrationo housing into wider areas.

Upgrading inadequate housing andslum areas.

Promoting urban creativity, culture,aesthetics, diversity.

Shaping values, tradition, norms andbehaviours (eg. in relation to energyuse, recycling, communal living andplace maintenance).

Protecting housing heritage andamiliarity o city (eg. preventingunnecessary social replacement/gentrication or completeredevelopment.

Managing economic activities andhrowth by strengthening housingprovision and housing markets.

Provision o necessary inrastructureand basic services to housing.

Providing serviced land or housing.

Strengthening entrepreneurship ocommunities, local building industryand enterprise.

Promoting local and traditionalbuilding materials and techniques.

Promoting regional and urbanregeneration.

Ensuring energy eciency, micro/generation, water and resourceeciency.

Green design, using sustainable

local construction and materials.Sanitation, preventing hazardousand polluting materials.

Aordable use o resources.

Improving resilience and adaptationo homes.

Empowering people and ensuringpublic participation.

Ensuring health, saety, well-being inresidences.

Creating a sense o community,sense o place, and identity.

Meeting secic needs and wants inhousing (including those related togender, age and health).

Providing access to inrastructureand public spaces.

Culturally responsive settlementsand house planning and design.

Imrpoving aesthetics, diversity andcultural sophistication o the builtenvironment and residence.

Helping community creativity (i.e.via amenities; aordable sporting,cultural and entertainment acilities.

Assisting peoples transitionromrural and slums areas to decenthousing or multiamily housing.

Ensuring housing aordability ordierent social groups.

Providing adequate residencesto raise labour productivity;ensuring housing is integrated withemployment.

Supporting domestic economicactivities and enterprise.

Promoting petty landlordism andsel-help housing.

Housing management andmaintenance.

Strengthening resilience and uture-proong o homes.

SUSTAINABLE HOUSING FOR SUSTAINABLE CITIES: A POLICY FRAMEWORK FOR DEVELOPING COUNTRIES

Source: UN-Habitat 2011c.

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FIGURE 1: SHORTCOMING OF THE PRESENT HOUSING POLICY RESPONSES.

Rapid and sustained urbanisation leadsto high housing demand.

Lack o aordable, accessible and desirable housingalternatives lead to the prevalence and expansion o

inormal settlements/slums.

Urban challenges: lack o ormalemployment low incomes, adjusting tonew liestyles and urban culture, etc.


Box 3: SuStaINaBlE HouSES

Sustainable houses are those that are designed, built and managed as:

Healthy, durable, sae and secure,

Aordable or the whole spectrum o incomes,

Using ecological low-energy and aordable building materials andtechnology,

Resilient to sustain potential natural disasters and climatic impacts,

Connected to decent, sae and aordable energy, water, sanitationand recycling acilities,

Using energy and water most eciently and equipped with certain on-site

renewable energy generation and water recycling capabilities, Not polluting the environment and protected rom external

pollutions,

Well connected to jobs, shops, health- and child-care, education andother services,

Properly integrated into, and enhancing, the social, cultural andeconomic abric o the local neighbourhood and the wider urban areas,

Properly run and maintained, timely renovated and retrotted.

Source: UN-Habitat, 2011c: 10.

Formal social housing is developed(Govt, Co-op., NGO; typically standardised

units at lowest-cost possible.

Sustainabilitydimensions seldom

eature in theseprogrammes or

policies.

Environmentally detrimental development: Lock in o energy demand and use.High operation costs or households.

Housing is oten not socially, culturally and eonomicaly responsive to households needs and values.

Slum upgrading is undertaken(by Govt., municipalities, NGOs, CBOs;housing units seldom considered, only

urban environment.

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Box 4: INCrEaSINg HouSINg dEmaNd IN our urBaN futurE

The worlds urban population is expected to grow rom 3.5 billion in 2010 to 6.2 by2050 or rom about 52% to 67% o the worlds total population. As much as 94% othis growth will be in developing regions (rom 2.6 billion by 2010 to 5.1 billion by 2050)(UN, 2011). The capacity o cities to deal with the population growth is challenged bythe structural problems o low development and poverty. The urbanization o povertysustains the rise o slums. It is estimated that 828 million people in developing regionswere living in slums in 2010, which constitute a third o the total urban population inthese regions (more than 70% in many countries in Sub-Saharan Arica). Although therelative share o slums in the total population is thought to be decreasing in most regions,the absolute number is still growing (see graph below) (UN-Habitat, 2010b).

Given a projected urban population increase by 1.43 billion between 2010 and 2030 and

adding to this the existing slum population, the number o people in the most urgentneed o housing within the next two decades can be estimated to be at least 2.25 billion.Assuming an average household size o 5 people, 450 million housing units have to bebuilt worldwide to accommodate this population that is, 22.5 million units annually ormore than 60 thousand units each day, rom this very moment. But even this is just a tipo the iceberg, as there is also the need to improve the inadequate housing conditions onon-slum residents and to replace existing housing stock that will come to the end o itslie or will be destroyed due to natural disasters and social conficts.

SUSTAINABLE HOUSING FOR SUSTAINABLE CITIES: A POLICY FRAMEWORK FOR DEVELOPING COUNTRIES

Source: UN-Habitat.

URban slUM popUlaTIon In DeVelopInG ReGIons In 1990 anD 2010 (MIllIon people).

0 40 80 120 160 200

1990

2010

Sub-SaharanArica

Millions

102.6

180.4

159.8

105.7

69.0

19.1

36

88.9

110.8

189.6

190.7

199.5

19.711.8

0.40.6

Southern Asia

Eastern Asia

Latin Americaand the Caribbean

South-Eastern Asia

Western Asia

North Arica

Oceania

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Box 5: multIplE BENEfItS of SuStaINaBlE HouSINg

Improved quality o lie and dignity o residence,

Aordable access to housing,

Improved health and lower incidents o illness, atalities and material losses, betterlabour productivity,

Better conditions or human development, employment, creativity and economic

growth, Durability and low maintenance cost,

Protection against natural hazards,

Improved eciency and savings on the use o energy, water and other physicalresources,

Better environmental protection and sanitary conditions,

Contribution towards climate adaptation and mitigation,

More sustainable and socially inclusive urban growth,

Social cohesion and political stability.

Inormal Palafta housing in Salvador, Brazil extending over Todos os Santos Bay. Matthew French/UN-Habitat.

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Solar water heating installed on social housing in Brazil. The units in the oreground are damaged,which highlights the importance o adequate maintenance. Matthew French/UN-Habitat.


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Te environmental sustainability o housingis concerned with the impacts o housing onthe environment and climate change, as wellas the impacts o the environment on housingitsel. More specically, there are three types

o the relationships between housing and theenvironment:

House building and operation requirevarious environmental resources, suchas building materials, water, energy andland;

Residential activities in humansettlements have direct ecological impacts

on local areas in terms o air and waterpollution, waste and damage o naturalecosystems;

Homes and their residents are alsothemselves exposed to variedenvironmental hazards, which mayemerge due to human activities (e.g. airand water pollution, lack o sanitation),due to natural actors (e.g. landslides,vector-born diseases such as malaria),

or due to the combination o naturaland human-made actors (e.g. climatechange).

Tus, housing provides an important meansor addressing local and global environmentalconcerns in relation to public health, energy,

water and material eciency and CO2emission, waste production and recycling,climate adaptation and environmental hazards

mitigation measures. Corresponding strategies

or improved environmental sustainability inhousing include the ollowing:

Reduce environmental ootprints romhousing in terms o energy and associated

GHG emissions, water, land and materialuse, as well as waste;

Ensure healthy housing and surroundingliving environments (including improvedsanitation, public health impact andreduced pollution);

Strengthen resilience and adaptation(robustness o design, hazards prevention,

greening).

Te rest o this chapter will review the ollowingcommon principles and considerations inrespect o environmental ootprint andresilience o housing:

Te whole liecycle o houses;

Residential densities and urban mobilityin neighbourhoods;

Mitigating environmental hazards andimproving green spaces;

Energy and resource eciencies;

Sustainable aordable building materialand practices;

Integrating housing into low-carbon

community inrastructure.

CHAPTER 2 EnvironmEntal sustainability of housing

02enVIRonMenTalsUsTaInabIlITY of HoUsInG

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2.1. ConsIDeR THeWHole lIfeCYCle ofResIDenTIal bUIlDInGs

Contemporary housing sector consumes largeamounts o scarce energy and other resourcesin its construction, maintenance and use.Tereore, housing activities potentiallyrepresent key mechanisms to better planenergy and resource consumption and tosupport climate change mitigation/adaptationeorts.

As ar as the implementation o housingprojects is concerned, it is important to

consider the whole liecycle o houses inquestion rom cradle to grave (able 2).Tus, the planning stage may address thechoice o the planned site and its impact onthe local environment, links to the city; qualityo the local built environment; density; publictransport and inrastructure; environmentalhazards. Design takes into considerationembodied energy and resource utilization andenables energy and water eciency; district

heating/cooling and micro-generation; wastemanagement; robustness and resilience, utureproong; possibility o upgrade. Constructionshould integrate saety and environmentalstandards; the use o local sustainable materials.Reurbishment should consider the choice oreurbishment material; energy ecient design;disturbance o the environment; managemento construction waste. At the nal stage o lie,a decision is taken whether demolish or reuseand recycle building components.

2.2. URban foRMs anDResIDenTIal DensITIes

I deciding on a new housing project, especiallyo a larger scale, it may be appropriate tostart not so much with the architecture anddesign, but with choosing the best location tomaximise sustainability. Tis is to recognisethat people live not simply in a house, but

in a neighbourhood and a settlement or acity. Sustainable development is seriouslycompromised by organizing cities around

urban sprawl and private car mobility.ransport is a main energy user and emittero CO2, as well as other pollutants. Morescattered residential environs require moreland, resources, and inrastructure (water, gas,electricity, roads) and lead to a disintegrationo the city space, including between sociallysegregated areas. Relatively compact andmixed-use mixed-income areas, which integratehousing, work, acilities and entertainment inclose proximity, are believed to constitute animportant strategy or reducing these negativeootprints. A more compact city also allowseasier, more aordable access by low-incomeresidents to urban services and employment

opportunities and a better sense o communityintegration and cohesion.

In large urban areas, an extension to thecompact city approach polycentricity ordecentralized concentration can redirectdevelopment pressures to new urban centres.Te strategy means that, i inevitable, peripheraldevelopment also proceeds in a compacttown-size mixed-use way. For this, planners

can envisage new housing developments tobe o a substantial size and located withinor near existing settlements, so that new cartravel distances are minimized. Developmentshould ideally be located near to a regional ormetropolitan public transportation system, sothat high levels o public transport accessibilitycan be provided. However, building ree-owing highway networks is likely to encouragethe sprawl o development and a strung-outcommunity (Banister and Anable, 2009).

However, it is not always that densicationprogrammes are accepted or welcomed in agiven social context. In already low-density areassuch programmes can meet residents protestsand sabotage rom powerul landowners. It is,thereore, important to prevent lock-in in low-density high-carbon liestyles rom the verybeginning by using the instruments o urbanplanning and building control eectively or

new-built areas.



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How dense is a compactneighbourhood?

Good environmental practices suggestmoderately-high densities or compactneighbourhoods. However, the actualdensity needs to be context-specic. Tere isa level beyond which density creates social,economic and environmental congestion andundermines sustainability. In some developingregions, many denser residential areas areassociated with poverty and overcrowding. Itis important in such cases to actually reducedensities and introduce new public, openand green spaces or recreation and leisure.

Furthermore, multi-oor residential estatesused or the resettlement o poor slum dwellersare not appropriate or many o them, asthe poor use their home or their inormalbusinesses that oten need access at the groundlevel. More generally, however, good urban

design creates attractive living environment bybalancing variously dense developments withaccess to green space, adequate inrastructureand good transport. Many European townsand cities show that the best solution lies in acompact-green city usion, where a relativelycompact built environment includes a diversityo densities and designs and maintains a goodcoherence with the landscape and greenenvironment (EU, 2004).

Related tasks include encouraging walking,cycling and public transport (rom, to, andbetween residential areas). Public transport isa crucial means to curb emissions rom travel.

For example, Mumbai with a higher shareo public bus transport and suburban railhas experienced a 60% reduction in energyand emissions compared to Delhi (Das andParikh, 2004). Tere is an interesting trendo adopting non-traditional means o public


TABLE 2: GUIDING MATRIX FOR ASSESSMENT OF ENVIRONMENTAL SUSTAINABILITY.

Source: UN-Habitat.

STAGE OF HOUSE LIFECYCLE EXAMPLES OF ENVIRONMENTAL SUSTAINABILITY CONSIDERATIONS

Planning stage Impact o the planned site on the local environment; relationships with the city; quality othe local built environment; mixed-use and density; polycentricity; inrastructure; publictransport; green areas; environmental hazards.

Building design Considering embodied energy and resource utilisation; enabling energy andwater eciency by design; integrating district heating asnd micro-generation; sustainablewaste management; green roos; robustness and resilience; uture-proong; possibility oupgrading; shaping o liestyles.

Construction Sae, environmentally-riendly, local aordable material; minimization o environmentalimpact rom building activity.

Operation Energy perormance; air-conditioning, air quality; pollution by residents and impact othe local pollution on residents, water use and water management, water recovery;comort and hygiene o homes; quality and energy eciency o the local inrastructureand transportation; property maintenance and management; waste management andrecycling; greening the area; natural hazards.

Reurbishment Choice o reurbishment material; energy ecient design; disturbance o the environment;management o construction waste.

End o lie Demolishing or reusing; recycling o building components; management o constructionwaste.

Reurbishment Choice o reurbishment material; energy ecient design; disturbance o the environment;management o construction waste.

End o lie Demolishing or reusing; recycling o building components; management o constructionwaste.

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transport, such as aerial ropeways whichcan also make remote residential areas moreaccessible. Examples include metrocables inMedellin, Colombia and Caracas, Venezuela,as well as Algerias aerial ropeway serving thecities o Skikda and lecern (UN-Habitat,2010a). Similar inrastructure is being builtto provide urban access rom some o theavelas in Rio de Janeiro, Brazil. Such meanso transportation use less material and energy,relatively cost-eective to install and are non-polluting.

2.3. MITIGaTeenVIRonMenTalHazaRDs anD IMpRoVeGReen spaCes

At the stage o planning and design o residen-tial projects, it is important to give an in-depthattention to contextual environmental hazards(existing or potential), including those relatedto the natural environment, such as oods,landslides, earthquakes, etc. Tese considera-

tions and related actions are a key ingrediento the housing resilient strategy.One simple strategy to mitigate environmen-tal hazards, while also protecting biodiversityand improving the health and quality o lie othe residents, is to ensure a good network ogreen spaces in the neighbourhoods. A greennetwork may include open spaces, waterways,gardens, woodlands, green corridors, wildliehabitats, and street trees. A green network notonly supports the natural ecological process-

es, but is also an essential part o local climatemanagement strategies important or bothclimate adaptation and mitigation.

Why do green areas matter ornatural hazard mitigation and climatemanagement?

Urban orestry and habitat restoration areamong the most cost-eective means or

carbon sequestration, as well as or urban airquality and runo management. Increasingthe amount and size o vegetation helps toreduce the amount o pollutants in the low

atmosphere; vegetation also removes carbondioxide during photosynthesis and emitsoxygen. Green areas have a cooling eectand mitigate heat waves (hotter-than-normal

weather) and urban heat island (highertemperatures in urban areas than in thecountryside) both o which have negativeimpacts on human health and biodiversity.Furthermore, vegetation reduces surace waterrun-o, thus preventing soil erosion andreducing the need o piped drainage. All othese eects are important in the context oincreased climate uncertainties and climate-related and other natural hazards.

Cities, even with a high density, have potentialor increasing green and open areas by, orexample, restoring browneld sites as parks orredeveloping closed landlls as green areas (Box6). Recycling o wasteland and derelict sitesand buildings gives an opportunity to cleanup contaminated sites, assist environment andsocial and economic regeneration. Some o thenovel approaches to greening the housing,although with a long tradition behind, include

also the integration o vegetation into the designo individual buildings, such as greening roosand walls, pocket parks, and the planting otrees in courtyards (Box 7).

2.4. enVIRonMenTalpeRfoRManCeof ResIDenTIalbUIlDInGs

Key concerns or the sustainable designo residential buildings lie with theirenvironmental perormance (energy eciencyand CO2 emissions; water eciency; materialeciency; pollution; waste management;relationships with the immediate area), healthimpact (air quality, water quality, hygiene),human comort (hydrothermal quality,acoustic quality, visual attractiveness, smellscontrol), as well as with the provision o

appropriate housing management. Some o themain elements o these issues are consideredbelow.



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Energy efciency in housing

Te generation o energy is the maincontributor to CO2 emissions and climatechange and it also results in many otherorms o environmental pollution. Housingis responsible or as much as a quarter o theglobal operational energy demand (embodiedenergy used in construction notwithstanding).Tis energy is used or space and water heatingand cooling, cooking, lighting, and operationo other energy-consuming activities withinhomes. Te use o this energy is in act anecessary condition to support lie and socialactivities in houses (able 3). Yet, as discussed

above, millions do not even have access toclean energy or struggle to aord it in sucientquantities because o the cost (leading to thephenomenon o energy poverty). Improvingenergy eciency and using renewable energyis a way to address this complex knot oenvironmental and social problems.

It is widely acknowledged that the cost oinvesting in the hosing energy eciency is

commonly smaller than gains achieved overa medium-term period rom resultant energysavings. Energy savings also mean avoidedenergy and CO2 generation. Tis also makesthe residential sector one o the most cost-eective (in act, protable) mechanisms orthe reduction o CO2 emissions.

o reduce energy demand and carbon ootprintrom residential buildings a range o solutionsmay be used (Golubchikov, 2009):

Planning and optimising the orientationand interrelation o buildings in space,as well as optimising walls and roosalbedo (by paint or greening), in order touse the opportunities oered by passiveheating, lighting and active shading,

Better insulating the structural elementso houses - walls, windows, doors, roos -in combination with a better ventilation(allows keeping houses warmer in cold

periods and colder in hot periods),

Installing energy ecient appliances orheating, cooling, cooking and lightingand ventilation,

Improving the eciency o utilitiessupplying houses with electricity, gas,

water, heating,

Developing local low-carbon powerplants servicing housing (e.g. districtheating and cooling based on combinedheat and power generation, renewableelectricity generation),

Equipping houses with renewableelectricity or heat generating installations(microgeneration),


Box 6: tHE rEHaBIlItatIoN of al-aZHar parK IN CaIro, EgYpt

Cairo, located amidst desert environments, has a particularly high residential density, withvery limited open space. By the mid-1990s, Cairo had only one square metre o openspace per resident. A 30 million USD Al-Azhar Public Park Project, which was opened in2005 by the Aga Khan Trust or Cultures Historic Cities Programme, was one solution tothis problem. The park was built on a 30-hectare site used as a dump or many centuries.The project has also rehabilitated the historic districts o Islamic Cairo, which is one o the

primary destinations or tourists, and has provided the residents with new opportunitiesor apprenticeships and employment.

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Reducing energy-intensive buildingmaterials and technologies used inhomebuilding,

Incentivising and disciplining householdsthrough energy metering and billing,

Capacity building activities to raiseawareness o the importance o energysavings and how it can be achieved.

Tese solutions are equally applicable toboth cold and warm environments, althoughclimatic considerations aect the use andpriority o particular building techniques. For

example, thermal insulation and solar gainsneed to be augmented in colder climates,

while a greater role is given to passive cooling,shading and wind tunnelling in hotter climates.Increased thermal mass is used in climates

where there are larger seasonal and day andnight variations in temperatures such in aridand colder climates, while it is less appropriatein tropical climates with smaller variations intemperatures (or more details on planning

and building energy-ecient houses withclimatic considerations see a complementaryguide Going Green: A Handbook of SustainableHousing Practices, UN-Habitat, 2012).

Many European countries, especially thoselocated in the colder environments, are quiteexperienced with very low-energy buildings.Comortable room temperature is achieved bymeans o highly ecient components, suchas high levels o insulation o walls, roos and

windows, heat or cold recovery rom recycledair, and the use o internal sources or heating(including existing household appliances andhuman heat). In order to minimise energyuse, the design o buildings may be requiredto t the specic characteristics o the location(in terms o climate, vegetation, topographyand geology, as well as the existing builtenvironment) and to use passive lighting,active shading, and energy-ecient appliances

and lighting (Figure 2). Remaining energydemand or electricity, the cooling system orhot water can come rom conventional sources

(electricity, gas, district heating) or romautonomous sources (microgeneration as

will be discussed below).

In principle, exiting technological solutionsalready allow individual houses and even wholecommunities to be completely sel-dependentor their energy needs much like the areas thatlack access to modern energy acilities, but, incontrast to them, with a ully modern qualityo lie. Zero-energy and zero-carbon citiesare already a realistic uture (Box 8). As willbe shown below, European Union standards,or example, are increasingly strengthenedin anticipation that all new buildings will be

required to be built to zero-energy standardsin the near uture.

How about indoor air qualityin energy efcient houses?

Modern highly energy-ecient houses arecharacterised by high levels o air tightness tostop warm or cold air losses. Tis requires extrameasures to ventilate houses. Commonly used

is mechanical ventilation with heat recovery.It operates by electricity and recovers heat orcold rom the used air indoor and exchangesit with the resh incoming air, thus providinggood air quality and comort. Te installationo such systems is, however, unaordable orthe majority in developing countries. And yet,it is not even necessary to have so high levels oinsulation. A knowledgeable use o traditionalmaterials and thermal mass, combined withnatural ventilation systems (e.g. wind-driven

cross ventilation or stack ventilation), maybe sucient to protect the house rom a coldor hot climate and to considerably reduce itsenergy demand, while still allowing the houseto breathe naturally. In any case, it is theimperative that indoor air quality must prevailover energy consideration, as inadequateventilation may damage the health muchmore than poor insulation particularly idirty energy or smoking is practiced indoor.

Building codes, model designs, and relatedmonitoring should include indoor air qualityconsiderations alongside energy.



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Source: Hendler and Thompson-Smeddle, 2009:14.

FIGURE 2: WINDOW OVERHANGS: USING PASSIVE LIGHTING AND ACTIVE SHADING.

Winter

Winter

Window overhangs Seasonal position o the sun

Summer Summer

Box 7: grEEN roofS

Green or vegetated roos reduce the over-heating o buildings in summer and provide abetter thermal insulation in winter, thus improving the buildings own energy perormancein addition to the positive eects or the neighbourhood as a whole. This coolingeect is also benecial or solar panels, as they currently work best at temperaturesup to 25C. Green roos also intercept storm-water runo and reduce the load on thebuildings drainage system, thereby extending its maintenance cycle. There are exampleso mandatory green roos as posited by recent policies in Toronto and Copenhagen;several cities in Austria, Switzerland, and Germany, ollowing the original experiences oBasel and Linz, have introduced either a compulsory greening o all fat rootops on newbuildings or additional subsidies or such measures.

CHAPTER 2 EnvironmEntal sustainability of housing | 19


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Embodied (embedded) energy

Te amount o energy used in buildings duringtheir ull liecycle is not only due to their directenergy consumption (energy-in-use), but alsodue to energy used during construction anddemolition. Concrete and steel manuacturing,extraction o raw materials, and transportationo construction materials contribute to theenergy use and carbon ootprint o a building.It is oten the case that buildings that areallegedly low-energy are built without dueconsideration o these embodied orms oenergy consumption. Although they consumelittle operational energy, their embodied

energy is such that over their liecycle, theircarbon ootprint can still be larger than thato the buildings with a lower operationaleciency but built in a sustainable way andusing local materials with low embodiedenergy. Te choice o materials and theirtransportation is among major considerationsor both construction and reurbishment.

An analysis o the relationship between

embodied energy and energy-in-use helpsensure a better choice o building materials.Tere is, or example, a variety o energymodelling sotware tools that can assistarchitects and engineers in optimising thebuilding design or reduced energy demand(with the caveat that all models have theirown limitations and never ully predict real-lie situations). A house designer needs tounderstand the environmental eect o allaspects o a house, including the delivery

cost o building materials, and the possibilityo disassembling building elements orreurbishment and recycling. An optimal wayto save embodied energy (and to reduce thecost) is to ensure that residential buildings lastlonger through, or example, integratingeatures rom the outset to reduce the need orcostly and wasteul repairs and retrots overthe medium term. One technique that hasbeen experimented with is integrating local

traditional sustainable and durable materialsinto preabricated construction (Box 9).

Water efciency

Water eciency at construction sites, in themanuacturing o building materials andin completed houses is a crucial element inachieving sustainable housing, given both thedepletion o resh water resources globallyand shortages o clean resh water supply inmany socially challenging environments. Teresidents o poor areas and slums in manydeveloping cities, especially women, spend alot o time o their lie in collecting water romremote sources, while also oten having to paydisproportionably high to the suppliers opotable water compared to their compatriots

enjoying a centralised water supply.

As regards to residential buildings, water istypically used or the ollowing purposes:

Bath and shower

oilet

Laundry

Cooking

Cleaning

Gardening

Water losses due to leaks.

Te ollowing sustainable practices arecommonly implemented:

Minimisation o water losses and leaks,

Rainwater and snowmelt harvestingsystems,

Re-use o water,

Water ecient installations in houses,

Waterless and low-ow technologies,

Te installation o water meteringsystems (or incentivising water saving).

Tese systems may range rom highlysophisticated and high-tech to low-cost thatcan be particularly appropriate to improve



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Box 8: low CarBoN CItIES

Some prominent examples o new low-energy low-carbon communities in developing

countries include Masdar City, currently being built in Abu Dhabi as a zero-carbon, zero-waste, car-ree municipality or 50,000 residents, which is thought to become the worldsrst climate-neutral city and Dongtan in China being planned as a low-carbon city toaccommodate 0.5 million people. While there are encouraging examples, their overallsustainability is oten disputed, as the projects may actually involve huge developmentcost (with associated energy and GHG impacts), be relatively isolated and exclude low-income people. It is important to act in existing urban districts, where there is a greaterpotential or paving a more sustainable uture. An example here includes the WesternHarbour (Vstra Hamnen) district o Malm, being turned rom a browneld area into anenvironmentally riendly town based on 100% renewable energy.


ENERGY SERVICES MINIMUM STANDARDS

Lighting 300 lumes or a minimum o 4 hours per night at household level.

Cooking and water heating 1 kg wooduel or 0.3 kg charcoal or 0.04 kg LPG or 0.2 litres o kerosene orbiouel per person per day, taking less than 30 minutes per household per dayto obtain;

Minimum efciency o improved solid uel stoves to be 40% greater than athree-stone fre in terms o uel use;

Annual mean concentrations o particulate matter (PM 2.5) < 10 g/m3 inhouseholds, with interim goals o 15 g/m3, 25 g/m3 and 35 g/m3;

Space heating Minimum daytime indoor air temperature o 18C;

Space cooling Maximum apparent indoor air temperature o 30C;

Rerigeration Households can extend lie o perishable products by a minimum o 50% overthat allowed by ambient storage;

Inormation andcommunications

People can communicate electronic inormation rom their household;

People can access electronic media relevant to their lives and livelihood in theirhousehold.

TABLE 3: MINIMUM STANDARDS FOR HOUSEHOLD ENERGY SERVICES TO SUPPORT DECENT

WELLBEING.

Source: Adapted from Practical Action, 2012:42.

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the quality o lie and alleviate water problemso the poor, as well as to alleviate the loadon existing reshwater provision systems.For example, even in very dense slum areas,guttering may be used to transport rainwaterrom the rootops to the storage vessels to beused or multiple household purposes and,i properly collected, stored and treated, orcooking (e.g. Gould and Nissen-Petersen,1999). Water used or cleaner purposes can becaptured and then used or dirtier purposes,as well as or irrigation, thus allowing a reuseo water. For example, in both developed anddeveloping countries large quantities o cleanresh water are used to ush toilets, whereas

this unction can be served by used water(so-called greywater), harvested rainwaterand many other kinds o water that areuncontaminated and ree o solid subsistence.

Regulations can be eective to improve watermanagement and recycling. For example, morethan 40,000 homes in Melbourne, Australia,are required to use Class A recycled water,metered and delivered separately in a distinctive

purple pipe, rather than potable water ortoilet ushing, washing cars and wateringoutdoor landscaping (OECD, 2010: 126).

Pollution o existing water systems byhousehold sewage and waste is anotherpersistent problem in many poor areas, whichneeds to be tackled seriously and prevented.Solutions here are closely interlinked with themeasures or improving sanitation and wastemanagement acilities (see Household waste

management and recyclingbelow).

Furthermore, both the quantity and qualityo water may also be saved already at thestage o construction in this regard, waterconservation and saving measures need to becommunicated to the construction workers toraise their awareness about an environmentally-conscious water usage.

Building codes or sustainable housing

Te development o appropriate technologyshould be ollowed by strengthened minimumeciency requirements or housing/buildingconstruction (incorporated into so-calledbuilding codes) or example, or energy,

water, air quality, as well as the ecologicalsaety o the used materials and technique.Building codes are mandatory in manydeveloped countries. Indeed, mandatorybuilding codes are ound to be among themost eective mechanisms or ensuringimproved perormance o buildings, includingor energy (Laustsen, 2008; Levine et al.,

2007). Such codes may be o national or localjurisdiction and may be dierentiated by typeso development and geographical conditions.

For example, the European Union (EU)already prepares or moving towards nearly-zero energy requirement or all new andretrotted buildings by 2020 and developscorresponding energy perormance standardsor buildings, or energy building codes (EU,

2010). Te idea is that only buildings that usevery little energy to operate will be permitted.New buildings will have to take this littleenergy rom nearby renewable energy sourcesor will generate it themselves. With properonsite generating capacities and permission ora dual-ow o electricity between the buildingand the common grid, some buildings will beable to send as much electricity back to the gridas they take rom it or even generate a surplus(known, respectively, as net-zero energy and

plus-energy buildings).

What are energy building codes?

Tese are building codes which regulatevarious energy-related elements o a new orrenovated building, such as the buildingsthermal design (e.g. thermal capacity,insulation, passive heating, thermal bridges);indoor climatic conditions and air quality;

the systems or heating, hot water, ventilation,cooling, lighting; and the design, positioningand orientation o the building. Tey usually



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Retroitting housing to improve environmental peormance in Czech Republic. Mathew French/UN-Habitat.


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speciy dierent parameters or dierentclimatic zones.

In developing countries too, targets can be putin place to ensure an increasing penetrationo passive, zero-energy, and zero-carbonbuildings with a caveat, however, o notintroducing universally strict regulationstoo ast (Box 10). Stringent building codesmay be uneasible or smaller developersand individual sel-builders, thus pushingsuch people into inormal practices. Indeed,mandatory codes are still rare in developingcountries, especially or residential buildings,and where they do exist are hardly ollowed.

In any case, building codes should be supportedby other instruments, including subsidies,capacity building and leadership development.Voluntary building codes and certicationsystems are used to this end too (Box 11). Oneo the recommendations advocated by the UN-HABIA or a ew decades now has been that

model (non-mandatory) sel-building designsbe developed or low income groups that canbe easily understood and implemented. Tesemay include a range o designs or dierentincomes and specic locations, all ensuringenergy and water eciency (UN-Habitat,2011d). Specially appointed ree or low-costinormation centres may urther support thelocal population on this matter.

2.5. sUsTaInablebUIlDInG MaTeRIalanD pRaCTICes

Sustainability o housingconstruction practices

Te actual construction process may createmassive environmental problems, includingnoise pollution, air and dust, and harmulcontamination through toxic waste. Te wasterom construction and demolition activities

Box 9: prEfaBrICatEd BuIldINgS

Preabricated housing construction (also know as pre-manuactured, o-site, fat pack,modular or volumetric) was popular in the post-WWII Europe as a means or providingquick aordable housing in mass quantities. Houses were usually designed or a shortlie with little consideration to aesthetics or energy eciency and have gained a poorreputation. Despite this, there has been a resurgence o interest to the pre-manuacturedtechnique as potentially environmentally-sustainable yet cost-eective. The advantageso the o-site technology include a reduced embodied energy (because o less vehicledeliveries and the economy o scale), waste reduction, reduced site disturbance, andbetter control over the used material and methods in actory settings. The houses can be

built to high environmental standards and can either ollow a pre-designed template orbe customised. A disadvantage is, however, that preabricated houses have to be boughtas ready-made products and, even i overall oering cost savings, can only be aorded bythe more afuent or incorporated developers and government. Still, some preabricatedcomponents can be standardised and subcontracted to poorer areas workshops, thusalso contributing to employment opportunities.

Furthermore, as one type o preabricated houses, portable buildings provide a quicksolution or accommodating reugees, victims o natural disaster or temporary labour since they are portable, the embodied energy is preserved when buildings are relocatedto another site. Care should be taken, however, because in many cases such temporary

houses can become permanent and this should also be considered in the design andplanning stage.



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is requently dumped illegally in dams,river courses and any available hollows. Teextraction o raw materials oten happens inrural areas, causing the degradation o landand ecosystems. Deorestation can also berelated to the building materials industry, astimber is oten obtained unsustainably romindigenous orests, which, given minimalbiomass and ecosystem replacement activitiesaterwards, leads to soil erosion, salinisationo watercourses, reduced precipitation and therelated problems.

Deective and inecient constructionmaterials and techniques can put at risk both

construction workers and the end-use residents.Sustainable house-building industry shouldprevent the use o harmul building materialsand nishes o residential buildings, whichconstitute a large share o the global toxic load.Construction practices should also promotesound and sae activities on construction sites,especially with regard to reduction in topsoiland vegetation losses, dust and noise pollution,and sae storage o harmul chemicals.

Which building materialsare unsae or health?

A study by World Health Organisation re-emphasises that the ollowing materialsshould be avoided in building construction,insulation and repair activities: asbestos, leadpaint, pressed wood products manuactured

with volatile organic compounds (e.g.ormaldehyde), arsenic in timber, batt

insulation materials containing ormaldehydes,and oam boards containing carcinogens andendocrine disruptors (WHO, 2011).

Aordable buildingtechniques and materials

Tere remains a huge potential or sustainableconstruction technologies and practicesinvolving ecological, healthy and sae materials

and environmentally riendly techniques even i there have been a good progress in thisregard (ollowing, or example, the Agenda

21 Sustainable Construction in DevelopingCountries; see CIB and UNEP-IEC,2002). Te adaptation o traditional buildingtechnologies - which are in harmony with localconditions, aordable, durable, reliable and,importantly, unctional or the modern lie - isespecially important.

Locally available traditional materials havemuch smaller environmental impact in contrastto materials such as bricks, concrete and iron mainly because o the lower embodied energy.Some well-known aordable materials withlow embodied energy include, or example:adobe or compressed earthen blocks, earthen

and lime-based plasters, the use o ash asalternatives to Portland cement, straw-bale,local stone, locally harvested rough sawnlumber, as well as other local biomass products(bagasse, hemp, bamboo), which are used asraw material to manuacture durable buildingmaterials (CIB and UNEP-IEC, 2002; UN-Habitat, 2011d). Tere has been a worldwideresurgence o interest in earth building.However, most soils do not contain the mix

o clay, silt and sand required or good brickmaking. Modern stabilization technology hasbroadened the range o natural soils suitableor making compressed stabilized earth blocks,and increased their strength and durability. Aninteresting type used in South Arica is alsoeathbag/sandbag constructions; sandbag wallscannot crack, are re proo, good insulators andresist water penetration (Roux and Alexander,2009).

Indigenous knowledge and techniques may beinvaluable or improved adaptive capacity ohouses by optimising constructions or naturalhazards. However, there should be careulconsiderations o the durability, resilience andresistance o the buildings made with the useo low-cost indigenous materials, especiallyin the areas that are prone to natural disaster.Suitability o particular materials or particularclimatic conditions and geographical hazards

has to be assessed beore advocating low-costlocal methods.



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Training should target saety in construction, as job-related accidents are common among poor constructionworkers in developing countries . Oleg Golubchikov/UN-Habitat.

Box 10: SHould ZEro-ENErgY BE a targEt for SuStaINaBlE HouSINg polICY?

A transition towards zero-energy zero-carbon housing is a revolutionary change that will

transorm the housing sector o the uture. Target-oriented instruments that require new

levels o technological perormance should, however, be reconciled with the housing

policys principles o aordability, accessibility and distributive justice. There is a risk o

targets such as zero-energy houses being transerred, in isolation rom other instruments

and objectives, to countries or regions with a limited welare state or undeveloped

housing policy. This is not only because these regions may lack immediate expertise on

building low-energy and yet healthy, resilient, sae and environmentally riendly houses,

but also because prioritising such targets may detract policy attention rom aordability

or adaptation and result in unbalanced practices. It is necessary instead to design policy

pathways to low-energy housing by nourishing certain policy development and cross-policies links seeking or an all-round sustainability. There are instruments that can guide

countries towards such a more balanced progression, including the UNECE Action Plan

or Energy Eciency in Housing, which highlights a number o policy packages or

moving progressively yet sustainably towards a low-energy housing sector.

Source: Golubchikov and Deda, 2012; UNECE, 2011



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A combination o traditional and modernmaterials may be an optimal way to take thebest o the two worlds. Te re-integrationo indigenous practices and materials cannotsimply replicate a model o a traditionalhouse. Teir use must adhere to the context ocontemporary requirements and technology.

Although these techniques have been deeplyrooted in the culture o dierent regions,today there is not much condence in thetechnical and economic easibility o thesetechniques partly due to many incorrectapplications recently. Furthermore, thetraditional methods o construction originatedin the rural context and are largely neglected

in cities as old-ashioned (Box 12). Havingsaid that, the traditional technologies serveas a springboard or research and innovationinto more sustainable technologies (CIB andUNEP-IEC, 2002).

Recycling in the construction industry

Tere is a need in a practice o producingbuildings and materials with a longer lie

span, and which are recyclable and disposableat a minimal environmental cost. Recyclingprovides a number o environmentaladvantages, especially in terms o a reducedconsumption o natural resources anddeposition o landll; saving energy in materialproduction and hence reduced pollution; andthe availability o more durable materials.

A signicant contribution to energy savings andavoiding GHG emissions is made by means o

incorporating into residential buildings re-usedmaterials (e.g. rom the demolition o previousbuildings) and by devising new buildings to besuitable or recycling at the end o their lie.Recycling may be possible or wood, metal,glass and limestone (although the health saetyo the used materials is obviously important toinvestigate).

Buildings with a solid basic structure can be

reurbished with less energy spent than in theconstruction o a brand new building, as thestructure and envelope incorporate a very high

proportion o the embodied energy even ithis strategy require certain compromises (e.g.unction and location in comparison to theideal new building).

2.6. InTeGRaTe HoUsInGInTo sUsTaInableCoMMUnITYInfRasTRUCTURe

Cogeneration and district heating

Houses have to be linked to adequate and low-

carbon urban inrastructure. District heatingand cooling systems are increasingly seen todayas the most energy ecient option to providespace and water heating in densely populatedurban areas. Tese systems have greatenvironmental and other advantages especially

when renewable sources or combined heat andpower are the energy providers.

Combined heat and power (CHP), or

cogeneration, involves producing thermal heatand electricity in one integrated process, sothat energy losses are minimised. Cogenerationis most advantageous i connected to districtheating (also known as community heating)and deployed at a city- or neighbourhood-scale. CHP plants can also provide cooling, bychilled water this is known as tri-generationor as combined cooling, heat and power.CHP plants become an essential element oradvanced district heating and cooling (DHC)

networks.

Distributed power andmicro generation

Renewable energy generated by individualsand communities can meet their own energyneeds, including through neighbourhood-scale power installations (so-called distributedgeneration) and even smaller building-

scale microgeneration. In this way, energygeneration is also brought closer to the usersreducing losses in energy transportation and



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improving community control over accessto energy. Dierent sources o renewableenergy can be used geothermal; wind; solar;biomass; and waste-to-energy. Te smallpower generators can be linked to the usualelectricity grid or district heating (albeit raisingissues o their compatibility) or, alternatively,supply electricity and/or heat directly to theconsumer (such as stand-alone renewablepower operating at distribution voltage level).

What are popular renewablemicrogeneration technologies?

Building-level microgeneration may include

heat pumps, small CHP plants, solar panels(PV) and solar water systems (thermalcollectors), wood pellet stoves, small windturbines, and other renewable technologies.

Although the eciencies o all microgenerationsystems are being improved over time, it issolar water systems that have been particularlypopular due to their relative eciency andsimplicity. For example, such systems havebeen compulsory to install on certain types o

new buildings in Israel, as well as in many citiesaround the world. In Barcelona, or example,Solar thermal ordinance requires all newbuildings and major renovations to use solarthermal collectors to supply at least 60% o theenergy used to heat water (OECD, 2010: 122).In many countries the installation o suchsystems is a requirement or being includedin public nancing programmes or housing e.g. or certain types o constructions undedby the Housing Development Administration

o urkey (OKI). German Agency orInternational Cooperation (GIZ, previouslyknown as GZ) has provided grants orinstalling solar water systems or low-incomeamilies in the ramework o the programmeso the 1,000 Roos in Brazil and the 25,000Solar Roos or Mexico. As one type o solar

water systems, sel-made batch heaters havebeen common in the Caribbean, Asia and

Arica.

Even i microgeneration oers savings on therunning cost or energy, high upront costsremain a serious barrier or its eective use atthe household level. Providing grants and loansor the residents to invest in microgeneration,nding other nancing incentives (e.g. eed-in-taris), or installing this in larger-scale socialor aordable rental housing developments willnot only improve access to clean energy, but

will also help poorer residents to save on theirliving cost (Practical Action, 2012). A care mustyet be taken about the reliability o the systemsand the arrangement or their maintenanceand repair, so that households do not actuallylose money in case o technical aults.

And yet community-scale micro-grids (locallycombined and centralised grids o electricitygeneration), especially in the context odeveloping countries and remote communities,help avoid high capital cost required orconnecting to national networked powergeneration and distribution. At the local scale,green energy also enables participation o localindustries in the development, deployment and

maintenance, creating opportunities or the localworkorce. Such community-based activitiesrepresent a good size or local companies orcooperatives to nance. Micro-grid may alsoinclude a mix o dierent energy sources orimproved reliability, combining green energy

with non-renewable uels, such as diesel, inso-called hybrid micro-grids (ARE, 2011).

Household waste managementand recycling

Integral to environmental sustainability isa well-designed waste management system.

Waste management involves the collection,transportation, processing and recycling o

waste materials.



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Why does waste matter orsustainable housing strategies?

Tere are a number o reasons:

Irresponsible or disorganised waste dis-posal creates various risks or both thehealth o the residents and the natural en-vironment, including air and water pollu-tion.

Waste places a heavy load on urban inra-structure and involves land use change;

Te decomposition o waste in landlls isone o the most important contributorsto the emissions o methane, and wasteis also responsible or carbon emissions iburned;

Waste is itsel the end o the liecycle oproducts, the continual production o

which consumes valuable resources andenergy;

Waste can ampliy negative local climateimpacts - or example, dumping o solid

waste can clog drainage channels and

cause local ooding.

Te provision o waste and recycling acilitiesnear housing should also be accompanied

with easy and ecient collection o wasteand recyclable materials. Tese acilities areundamental or creating a good qualityneighbourhood and sustainable housing.

Waste prevention, recycling, composting, andenergy recovery rom household waste are alsogood environmental and climatic practices,helping to achieve sustainability. For example,in some environmentally-concerned countrieslike Sweden less than 20% o household wasteis deposited as landll.

Recycling o domestic waste involves the use owaste as a resource or other products. Manymaterials may be recycled including glass, paper,metal, plastic, textiles and electronics. Pre-sorted biodegradable waste (e.g. kitchen andgarden waste; sewage sludge) may be used orcomposting. However, urban waste recyclingand composting requires eective municipalinrastructure or the collection o thesematerials, their sorting and urther processing.

Box 11: ENvIroNmENtal aSSESSmENt aNd INtErNatIoNal ratINg SYStEmS for

BuIldINgS

Voluntary building codes and environmental assessment systems have been eective in

promoting green buildings. These may also be useul or the development o national

building codes in developing countries. Examples o internationally-renowned rating

systems include BREEAM (BRE Environmental Assessment Method) in the UK, LEED(Leadership in Energy and Environmental Design) in the US, Green Star in Australia, and

HQE (Haute Qualit Environnementale) in France. In order to rate a building, they include

considerations o the impacts o the assessed buildings on the environment, health and

wellbeing. These certication systems have been also exported beyond their origin to now

rate many buildings worldwide, including in developing countries. They may also aect

governments decisions, including in choosing or prioritising projects or public subsidies.

For example, BREEAM assessment methods or housing have been incorporated into

national standards in the UK known as the Code or Sustainable Homes, certain levels o

which become mandatory to achieve or various housing developments. O interest are

also standards that are developed or the assessment o building materials and designoptions by International Standards Organisation (ISO).



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Box 12: a CulturallY-awarE uSE of low-CoSt BuIldINg tECHNIquES

The eort o World Hands Project in Juarez, Mexico, highlights the importance o culturally-aware approaches to low-cost sustainable homes. The project was originally designed touse reclai

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Sustainable Housing for Sustainable Cities