Attaining Sustainability through Construction Procurement in
Singapore
G. Ofori
Department of Building, National University of Singapore,
4 Architecture Drive, Singapore 117566,
Email: bdgofori@nus.edu.sg
Abstract: Procurement is considered to be the key to performance improvement in the
construction industry. Clients, through their bargaining power, can provide incentives and
rewards to encourage good performance. Pressure from end purchasers and users would
encourage clients to adopt the right policies in these regards. To enable them to do this, both
clients and end purchasers require education and the correct information. A sound regulatory
framework would also encourage appropriate action by all parties involved.
This paper considers recent trends in sustainable development in Singapore. It discusses
efforts being made by clients (especially private clients) to attain sustainability on their
projects through the approaches to procurement which they adopt. The paper first considers
the importance of sustainability and the measures taken at the broad industry level, for
example, through regulations such as those made under the Environmental Pollution Act
2001 (for example, the need to employ an Environmental Control Officer) and policy
guidelines, such as the Green Mark scheme of the Building and Construction Authority
(BCA). It is suggested in the paper that sustainability should be one of the key words of the
construction industry and its clients; its attainment should be an objective, and a paramount
consideration on all projects. Clients should evaluate the track record of both consultants and
contractors in terms of sustainability during the procurement process. A concerted effort by
government, industry and clients should be made.
Keywords: Client Action, Education, Performance Information, Sustainability, The Future
1. Introduction
Many studies show that the procurement approach adopted on a construction project leads
efforts in improving performance. The theme of the W92 symposium in Montreal, Canada in
1997 was “Procurement – The way forward”. The conclusions reached at the symposium
confirmed the theme (Davidson, 1998: xi):
On the power of procurement, there was little doubt expressed by the Symposium
participants… The importance of the building owner’s decision was clearly
recognised as fundamental in setting up the framework for all subsequent
activities…
The potential of clients using procurement to influence progress towards greater contribution
of the construction industry to the efforts to attain sustainable development is also
highlighted. The Commission of the European Union (2004) urges member countries to,
among other actions, introduce sustainability requirements into governments’ tendering
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procedures. The Working Group for Sustainable Construction (2001) suggests that clients,
especially public clients, should take the lead in promoting sustainability in construction;
clients should measure and report their progress in promoting sustainability in construction;
and sustainability impacts and their mitigation should be addressed during the planning and
design stages. The Group recommends that (p. 16):
a. Clients should be encouraged to assess tenders on the basis of the economically
most advantageous tender, balancing price, quality and life cycle costs, for which
the quality assessment criteria should include sustainability factors.
b. The award of contracts on the basis of ‘concessions’ linked to solutions on the
basis of ‘facilities management’ taking increased account of life cycle costs … may
have its advantages.
c. Tenderers may be encouraged to put forward alternative technical solutions that
take into account environmental aspects.
The Working Group (2001) discusses sustainable construction programmes in several
European countries, in which the procurement process features prominently. It notes that:
…conscious of their responsibility regarding the realization of sustainable
development, more and more public purchasers wish to, and actually do, integrate
environmental considerations into their procurement policy (p. 15).
The UK government has incorporated sustainability in all its procurement of goods and
services, under the national strategic framework for attaining sustainability, “Securing the
Future” (HM Government, 2005). Several examples are given in this paper. The Oxford
Radcliffe Hospitals NHS Trust introduced “sustainable solutions from a brief through design,
into construction” (Office of Government Commerce, 2006: 1). The clients and contractors
prepared sustainability and biodiversity action plans. Measures taken on the site included:
engagement of a waste management company to segregate and dispose of waste, leading to
the diversion of over 90% of waste from landfills; introduction of a green transport plan for
the workers; selection of linoleum flooring manufactured from renewable materials, which
has a long replacement life cycle and is biodegradable; use of ceiling tiles made of 30% postindustrial waste; and collaboration with paint supplier to supply paint in 10 litre metal cans,
making polyethylene terephthalate cans unnecessary.
2. Aims and Objectives of Paper
The aim of this paper is to discuss how clients can contribute to the efforts to attain
sustainability on their construction projects through the procurement processes they adopt.
The objectives of the paper are to:
1. consider the nature and challenges of sustainable development with respect to
construction, concentrating on environmental sustainability
2. discuss recent trends in sustainable development in Singapore, focusing on building, and
considering mainly the efforts of clients to attain sustainability on their projects through
the approaches to procurement which they adopt
3. suggest initiatives which can be taken to make the attainment of sustainability a
paramount consideration on all building projects.
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3. Sustainable Development and Sustainable Construction
Pearce (2006) analyses various definitions of “sustainable development” and notes that it is a
value-laden expression. Du Plessis (2005) also discusses many definitions of sustainable
development and “sustainable construction”. “Sustainable development” has several aspects.
For example, the Hong Kong government adopted the following guiding principles of
sustainability (Planning Department and Environmental Resources Management (2000):
economy; health and hygiene; natural resources; social; biodiversity; cultural vibrancy;
environmental quality; and mobility. This paper focuses on the environmental aspects of
sustainability. This is important with respect to building owing to the environmental impact
of buildings. Lutzkendorf and Lorenz (2005), and Gluch and Stenberg (2006) provide a
catalogue of these impacts. Chen et al. (2005) highlight the following environmental
challenges from the development of housing estates in Beijing, China: inefficient land use;
water shortage; air pollution; traffic congestion; deterioration of the ecological system; high
energy consumption; and high volumes of waste.
The literature highlights the need for a cradle to grave approach in the effort to attain
sustainability in construction, with action being taken at all the stages of the process (see, for
example, Sjostrom, 1999). Actions to protect and enhance the environment can be taken at
many levels. For example, governments provide the statutory and policy frameworks for
action by business enterprises and individuals. They also offer incentives and support
mechanisms including advisory services.
3.1 Sustainable Procurement
In a paper on their sustainable procurement policies, the Office of Government Commerce
and Department for Environment, Food and Rural Affairs (2003: 2) note:
Sustainable development means achieving four objectives at the same time: effective
protection of the environment; prudent use of natural resources; social progress
which recognizes the needs of everyone; maintenance of high and stable levels of
economic growth and employment.
Thus, sustainable procurement would seek to attain these objectives, within the context of
achieving value for money.
Knowledgeable clients have influenced the process by which their buildings have been
designed and constructed. The Environment Agency (2006: 2) notes:
We have made progress as a public sector client adopting the principles of
sustainable construction. But we could do more. We will identify sustainable
construction targets when developing our capital projects, such as reducing waste
and pollution incidents, setting targets for recycling aggregates or enhancing
biodiversity. …we will adjust our appraisal framework and procurement practice so
that sustainable construction objectives are taken into account.
To influence the construction process effectively, clients require knowledge and commitment.
The Office of Government Commerce and Department for Environment, Food and Rural
Affairs (2003) adopt the environmental purchasing hierarchy suggested by Morton (2002):
dispose/end of life management; recycle; re-use; reduce; eliminate; and rethink. The Central
Procurement Directorate (http://www.cpdnii.gov.uk) proposes the following 12 principles
which govern public procurement: (i) accountability; (ii) competitive supply; (iii) consistency
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of application of general procurement policy across public sector; (iv) effectiveness in
meeting the commercial, regulatory and socio-economic goals of government; (v) efficiency
and cost effectiveness in all procurement processes; (vi) fair dealing in ensuring suppliers are
treated fairly and without unfair discrimination; (vii) integration of procurement policies with
other economic and social policies; (viii) integrity (no corruption of collusion with suppliers
and others; (ix) informed decision making; (x) legality; (xi) responsiveness; (xii) and
transparency.
Themes of sustainable construction procurement offered by the UK Office of Government
Commerce (2000) are: (i) re-use existing built assets; (ii) design for minimum waste; (iii) aim
for lean construction; (iv) minimise energy in construction; (v) minimise energy in use; (vi)
do not pollute; (vii) preserve and enhance bio-diversity; (viii) conserve water resources; (ix)
respect people and their local environment; and (x) set targets. Similarly, the action plan of
the Government Construction Clients Group aimed to achieve, between 2004 and 2006:
procurement in line with value for money principles on the basis of whole life costs; less
waste during construction and in operation; targets for energy and water consumption for new
projects that meet the least current best practice for construction type; protection of habitat
and species; targets developed in terms of “respect for people” for all procurement; an
increased number of new and refurbished projects achieving at least “very good” rating under
an established assessment scheme; increased engagement with local communities in decision
making; and improved industry performance. By March 2006, all projects of members of the
Group (an increase from 25% in 2004) would have criteria for evaluation of sustainability
included in the procurement procedures.
4. Trends in Singapore
4.1 Importance of Sustainability in Singapore
Singapore has a comprehensive body of statutes, regulations and codes which govern
activities, outline good practice, provide norms and targets, prohibit harmful actions and
products, and set sanctions. These include the Environmental Pollution Control Act and the
State Lands Encroachments Act. The institutional framework for forming, implementing and
enforcing policies is headed by the National Environment Agency (NEA) which was formed
in 2002. Its vision is: “an enterprising agency, embracing all in caring for our clean and
healthy environment - today, for tomorrow” (http://www.nea.gov.sg/). Its mission is: “To
ensure a sustainable quality environment in Singapore”. It seeks to accomplish these by
working with the community through: facilitating and providing environmental services;
promoting environment-related industries; and training and public education.
The framework for action to attain sustainable development in Singapore is the national
Green Plan, first published in 1992. Over 17,000 people participated in the formulation of the
current Singapore Green Plan 2012 (2006 edition) (Ministry of the Environment and Water
Resources, 2006). It is a ten-year blueprint with the following focus areas: (i) air and climate
change; (ii) water; (iii) waste management; (iv) nature; (v) public health; and (vi)
international environmental relations. Two aspects of SGP2012 which may be discussed this
paper are: “clean land” and “clean air”. To reduce the volume of waste generated in
Singapore, SGP2012 proposes: volume reduction by incineration; waste recycling; reducing
landfilled waste; and waste minimisation. With limited land and only one landfill site,
Singapore currently incinerates about 90% of waste generated. C&D waste such as concrete
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products, are prominent in the non-incinerable waste which must be landfilled. SGP2012
aims to achieve “Zero Landfill”; this has implications for construction.
Singapore has maintained a high standard of air quality by setting stringent emission
standards, promoting energy efficiency, and using energy sources that emit less pollutants
such as natural gas. The concentrations of major air pollutants (sulphur dioxide, nitrogen
oxides, carbon monoxide, ozone and particulate matter below 10 microns) are below the
levels set by the World Health Organisation (http://www.nea.gov.sg). SGP2012 offers the
following proposals on clean air: introduce a framework, programmes and policies to control
the emission of air pollutants; leverage on regional co-operation in the control of haze; focus
on targeted sectors to promote energy conservation and the use of cleaner energy sources
such as compressed natural gas, fuel cells and solar cells; engage and encourage industries to
implement effective air pollution control measures; and explore and test new technologies
which are suitable for Singapore to adopt.
4.2 Measures for Construction Industry
Many regulations have been introduced to guide and control building activities in Singapore
in order to reduce their environmental impact. These relate to: (i) design, such as the
mandatory overall thermal transmittance values of building facades; and (ii) management,
such as the regulation under Section 62 of the Environmental Public Health Act (Chapter 95),
and the Environmental Public Health (Employment of Environmental Control Officers) Order
1999 requiring the occupier of the construction site to employ an Environmental Control
Officer on a full-time basis if the contract sum of the construction project is $50 million
(US$1 = S$1.58) or more, or part-time for projects with contract sum between $10 million
and $50 million to supervise and promote environmental public health on the site
(http://app.nea.gov.sg/cms/htdocs/article.asp?pid=951).
Contractors which wish to undertake public-sector projects are required to register with the
BCA (which is responsible for the development of the construction industry). The criteria for
registration for large and medium-sized firms include certification to the ISO 9001 quality
management system (since 1999), ISO 14001 environmental management system (since
2004) and ISO 18000 health and safety management systems.
The BCA launched the Green Mark for Buildings Scheme (Green Mark) in January 2005.
The aim was: “to move Singapore’s building and construction industry towards environmentfriendly buildings and help strengthen Singapore’s position as a global city committed to
balancing its development with care for the environment” (Foo, 2005). The objectives of
Green Mark are to: promote environmental sustainability in the construction industry and
raise the awareness among developers, owners and professionals of the environmental impact
of their projects; recognise building owners and developers who adopt practices that are
environmentally conscious and socially responsible; and identify best practices in the design,
construction, management and operation of buildings.
Under Green Mark, new buildings are assessed in terms of: (i) Energy Efficiency; (ii) Water
Efficiency; (iii) Site and Project Development and Management; (iv) Indoor Environmental
Quality and Environmental Protection; and (v) Innovation. On existing buildings, “Site and
Project Development and Management” is replaced with “Building Management and
Operations”. To ensure that buildings given the Green Mark are well maintained, they are
assessed every two years. There are four levels of Green Mark ratings: Platinum Star,
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Platinum, Gold and Silver. The Green Mark provides a label of environmental performance
to guide end purchasers and users. It also provides information on the track record of
practitioners and firms to facilitate selection during procurement.
4.3 Efforts by Clients
In this section, the sustainable procurement practices of some clients in Singapore are
presented. The case study of one large developer is followed by examples of other clients.
4.3.1 Case Study: City Developments Ltd
City Developments Ltd (CDL) has a large portfolio of properties in Singapore and overseas,
including an international chain of hotels. Its environmental policies and practices are now
discussed.
CDL declares that it is “committed to offering a living environment that is conducive for a
healthy and comfortable lifestyle”. It has formulated an Environment, Health and Safety
Policy to monitor and control the impact of the firm’s activities on the environment. CDL
was the first private property developer in Singapore to be awarded both ISO 14000 and
OHSAS 18000 certification for property development and project management services (in
2003). The company believes that it takes measures to raise environmental and health and
safety standards in all its projects to deliver quality buildings that are easy to maintain and
efficient to operate. For example, CDL indicates that it introduces innovative ecological
features into the homes it builds to promote greener living. Its homebuyers are encouraged to
“recycle, reduce and reuse”; this is supported by the firm’s Care and Recycle Programmes at
some residential developments. In planning a new development, CDL makes efforts to
preserve the natural foliage and integrate the natural terrain into its landscaping. Table 1
shows some environmental features in three of its condominium projects including Savannah
Condo Park, the firm’s first “eco-condo”.
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Table 1: Environment-friendly features in some CDL residential condominiums in Singapore
Savannah
Condo Park
Water taps built in planter boxes for residents to maintain high-rise
gardens.
Lush landscaping.
Energy saving lighting fitted along ventilation walls, boundary
fences and other common areas
Rooftop air turbines that provide energy efficient cooling and
reduces utility bills
Energy-saving air-conditioning systems for all houses.
Eco-friendly architectural design that creates convection wind to
cool the residence naturally
Specially designed roof gardens that provide rooftop insulation to
minimise dependency on air-conditioning
Solar panels installed in the clubhouse to convert solar energy into
usable electricity to be be used in selected rooms and water heaters
for the clubhouse.
An odourless and mechanised pneumatic waste disposal system that
removes solid waste from refuse chutes in individual homes to a
sealed compactor within the bin centre or a mobile truck.
A designated green corner with colour coded bins placed at strategic
locations to encourage residents to recycle.
Use of environment-friendly building materials such as recycled
wood chips in laminated flooring instead of timber to help conserve
natural resources and the environment.
An ecological pond that maintains water clarity and controls odour,
algae and bacteria growth by recirculating the water through an
aerobically active filter bed.
Provision of bicycle racks to encourage residents to cycle as an
alternative to driving.
Source: http://www.cdl.com.sg/cdl2.nsf/ws.htm
Changi Rise
Condominium
Goldenhill
Villas
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
CDL requires contractors and subcontractors it engages, and consultants it commissions to be
certified to ISO 14001. Its contractors must also meet criteria including material waste. It
awards the 5-Star Environmental, Health and Safety Award to firms meeting the stringent
comprehensive evaluation criteria. CDL’s sustainable procurement practices have shown
results by influencing its business partners. Consultancy and construction firms which
undertake its projects have some of the best practices in Singapore’s construction industry.
Tiong Seng Contractors (Pte) Ltd won the coveted Construction 21 Best Practice Award in
2006 (it was the only winner that year) for implementing a wastewater recycling system for
silt water management and recycling for use in construction. The system had been procured
and adapted with the encouragement of CDL, and used on several of its projects by the
contractor. CDL projects have also won many awards for good environmental performance.
Table 2 presents the environmentally responsible features of CDL’s projects which won (four
of the total of eight) Green Mark award in 2006.
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Table 2: Environmentally responsible features of CDL projects which won Green Mark Gold
in 2006
Residential
Project
City Square
Residences
Environmentally responsible features
* Construction using diaphragm wall uses less strutting materials
* Extensive use of solar-powered light-emitting tiles, pole lights, bollard lights in landscaping
* Dual chute pneumatic refuse collection system segregates recyclable and non-recyclable waste
* Extensive use of sunpipes to send light into the three basement levels
* Use of silt treatment and water recycling plant to recycle treated water for washing and cleaning
St Regis Hotel
* Self-cleaning ceramic façade cladding system saves water
& Residences
* Condensate water recycling saves up to 19,300m3 of water per year
* “Wetstep” silt water treatment system saves 3,210 m3 of water per month
* Motion detection system is integrated with lighting for private lift lobbies
* Dual chute pneumatic refuse collection system segregates recyclable and non-recyclable waste
King’s Plot 3
* During construction, water treatment system was used to recycle treated water for washing and
Residences
cleaning
* All units are supplied with 4 ticks energy labeled air conditioning systems
* all units are provided with dimmer controls in living/dining and master bedrooms
* Tanks on fourth storey collect rainwater to be used for watering plantson ground floor by
gravity fall
The Sail @
* Construction using peanut-shaped diaphragm wall eliminated strutting, making the working
Marina Bay
environment safer and cleaner
* Staircase shelter – uses less concrete and steel for construction and less materials for accessories
* Solar powered system for heating pool and powering aircraft warning lights
* Dual chute pneumatic refuse collection system segregates recyclable and non-recyclable waste
Source: BCA, 2006
CDL was one of only two companies to be awarded the Singapore Green Plan 2012 Award in
2005. This award recognises individuals and organisations which are considered to make
outstanding contributions towards the attainment of environmental sustainability in
Singapore. The firm also won the prestigious Singapore Environmental Achievement Award
2004. CDL is one of very few companies in the world which meet FTSE4Good’s Socially
Responsible Investments standards of corporate social responsibility. The firm was
recognised by FTSE4Good for working towards environmental sustainability, and developing
positive relationships with stakeholders. CDL won the Merit Award for Best Public Relations
Work for the Environment at the PR in the Service of Mankind (PRISM) Awards 2002. It
also won the Green Leaf Award in 2000 (administered by the then Ministry of the
Environment) for being the first developer in Singapore to install eco-friendly lifts and
innovative pneumatic refuse collection systems in selected condominiums, and for setting
aside large proportions of site area for greenery and landscaped gardens in its projects.
4.3.2 Other Private Developers
Some other clients have good records in sustainable procurement. Table 3 shows the
environmental features of other projects (other than CDL works) which won the Green Mark
award in 2006.
The two projects which won the Green Mark Platinum award in 2006 were Republic
Polytechnic and Tan Tock Seng Hospital (BCA, 2006). The knowledgeable clients’
procurement approaches led to many environmental innovations on both projects. Republic
Polytechnic has a “Campus in the Park” look. Its features include: use of photovoltaic solar
energy for general lighting and power; a pneumatic waste conveyance system; and multiple
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ventilation modes for the sports hall. Tan Tock Seng Hospital uses hydrogen fuel cell
technology as back-up power; a heat exchanger supplies hot water to the kitchen by
extracting the air conditioning system’s waste heat; and energy saving dual sensor (carbon
dioxide and temperature) system controls mechanical ventilation in the basement carpark.
Table 3: Environmentally responsible features of residential projects of developers other than
CDL which won Green Mark Gold in 2006
Residential project
(Developer)
RiverGate
(Riverwalk Promenade
Pte Ltd)
The Tresor
(Keppel Land Realty
Pte Ltd)
The Azure
(FCL View Pte Ltd)
Varsity Park
Condominium
(CapitaLand
Residential Singapore)
Source: BCA, 2006
Environmentally responsible features
* Sprawling landscape on the ground; green vista is extended vertically to top of towers
* Water drip line system, operating with timers and rain sensors, are installed in the sky and
roof gardens
* All systems have dual flushing system water closets
all units are provided with inverter multi-split air-conditioning systems
* Guard houses use recycled water collected from integrated basins to flush toilets
* Waterless urinal in clubhouse toilet
* Ductless mechanical ventilation fans in basement car park
* Use of recycled plastic in equipment in children’s playground
* Solar powered light-emitting tiles, pole lamps, bollard lights in landscaped areas; solar
powered water heater in clubhouse changing room showers
* Use of sunpipes to send light into basement carpark
* Environmentally friendly lightweight plastic grid for turfing along fire engine access way
* Pneumatic refuse collection system segregates recyclable and non-recyclable waste
* Blocks of buildings are oriented to reduce direct sunlight into apartment units
* Basement carpark has about 20% opening for natural light and ventilation, eliminating the
need for full mechanical ventilation and water sprinkler fire-fighting system
* Gearless traction elevator
5. Recommendations
A national construction industry development strategy should be formulated for each country.
It should aim to enhance the performance of the industry from all the key perspectives: cost,
time, quality, the environment, health, and safety. The environmental perspective should be
given pride of place owing to its long-term benefits to end purchasers and society. This
blueprint should highlight the roles of each of the stakeholders in the efforts to realise the
objectives of the initiatives, and provide for an administrative mechanism for implementing
the strategies.
Clients should incorporate the protection of the environment in their corporate missions,
policies and objectives, and procurement approaches. Clients should evaluate the track
record of consultants and contractors in terms of sustainability during the procurement
process, and assess their performance on the projects in these regards.
Clients, consultants and contractors should be educated on environmental issues of
construction. The educational programme should be developed and delivered by the national
agency for construction; the professional institutions; the contractors’ association; and the
clients’ association. End purchasers and users should also be educated on sustainable
development and sustainable construction. They would then constitute a market force which
would compel developers to adopt sustainable procurement practices.
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Smaller developers’ companies could pool their resources, to enable them to exercise control
of the features of the main items they procure, and to gain economies of scale. End
purchasers and users in each country could also form associations to represent their interests
to clients and the design team.
Projects utilising best sustainable procurement practices, both locally and overseas, should be
documented by the construction industry development agency, and the case studies
disseminated among practitioners.
6. Conclusion
Sustainability should be one of the key words of the construction industry and its clients. Its
attainment should be an objective, and a paramount consideration on all projects. For the
individual project, arguably the most relevant aspect is the environmental one. Clients, as
prime movers of projects, can play a significant role in enhancing the environmental
performance of the design and construction teams. There is scope for applying the principles
of sustainable procurement on all construction projects.
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