Perhaps the most important infl uence on construction and the professions
since the turn of the millennium is the prominence given to
sustainable issues.
If this book had been written ten years ago, then sustainability
would not have been an issue; seven years ago sustainability issues
were starting to be discussed, but were considered only to be of interest
to tree-hugging cranks. Welcome to the second decade of the twentyfi
rst century where sustainability and the need to be badged a green
construction organisation is seen to be vital to maintain market share.
26 Quantity Surveyor’s Pocket Book
The Stern Review (2006) came to the conclusion that ‘an overwhelming
body of scientifi c evidence now clearly indicates that climate
change is a serious and urgent issue. The Earth’s climate is
rapidly changing, mainly as a result of increases in greenhouse gases
caused by human activities’. As illustrated in Figure 1.3, buildings
(domestic and non-domestic) account for nearly 50% of UK carbon
emissions and it is for this reason that such importance has been
given both by the European Union and the UK governments on the
introduction of Energy Performance Certifi cates (EPCs) and Display
Energy Certifi cates (DECs). It is the stated long-term goal in the UK
to reduce carbon emissions by 60% by 2050.
Legislative background
The European Union Directive 2002/91/EC on the Energy Performance
of Buildings Directive (EPBD) became law on 4 January 2003.
This made it mandatory for EPCs and Display Energy Certifi cates
(DEC) to be available for constructed, marketed or rented buildings
including non-dwellings by 4 January 2009, at the latest. The EU
directive was implemented in the UK by means of:
- 22%
- 1%
- 27%
- 19%
- 31%
Industrial Process
Agriculture
Domestic Buildings
Non-domestic Buildings
Transport
The quantity surveyor and the construction industry 27
• The Housing Act 2004, Section 134
• The Home Information Pack (No. 2) Regulations 2007
• The Energy Performance of Buildings (Certifi cate and Inspections)
(England and Wales) Regulations 2007/991
• Similar enabling legislation was introduced for the devolved administrations
of Scotland (The Housing (Scotland) Act 2006) and
Northern Ireland.
Even before the full implementation of the EPBD, plans were at an
advanced stage to revise the legislation with, amongst other things,
a public consultation that closed in July 2008. It is expected that by
2013 the new directive, currently referred to as EPBD2, will include:
• Further steps to act on carbon emissions
• A reduction in the threshold for fl oor areas that is included in the
legislation
Prior to the introduction of EPCs a series of other models were developed
to assess the energy performance of buildings across the UK,
namely EcoHomes and BREEAM.
EcoHomes points
Now superseded by the Code for Sustainable Homes, except in
Scotland, some development projects still have a requirement for this
assessment.
EcoHomes assesses the green performance of houses over a
number of criteria by reducing:
• CO2 emissions from transport and operational energy
• Main water consumption
• The impact of materials used
• Pollutants harmful to the atmosphere
and by:
• Improving the indoor environment.
BREEAM
The Building Research Establishment Assessment Method (BREEAM)
has been developed to assess the environmental performance of
both new and existing buildings over the following areas:
• Management: overall management policy, commissioning and procedural
issues
28 Quantity Surveyor’s Pocket Book
• Energy use
• Health and well-being
• Pollution
• Transport
• Land use
• Ecology
• Materials, and
• Water, consumption and effi ciency.
Unlike EcoHomes’ points, BREEAM covers a range of building
types, such as: offi ces, industrial units, retail units, schools and
even leisure centres. BREEAM measures the environmental performance
of buildings by awarding credits for achieving levels of
performance. The cost of having a BREEAM assessment can be
considerable.
What is sustainability?
There are many defi nitions, as with any new buzz term, people queue
up to add their defi nition in order to gain their fi ve minutes of fame!
In reality, it would appear to mean different things to different people
in different parts of the world, depending on their circumstances.
Consequently, there may never be a consensus view on its exact
meaning. However, one way of looking at sustainability is ‘ The ways
in which built assets are procured and erected, used and operated,
maintained and repaired, modernised and rehabilitated and reused
or demolished and recycled constitutes the complete life cycle of sustainable
construction activities.’
Why is construction signifi cant in the sustainability big picture?
• Over 90 million tonnes of construction and demolition waste arises
annually in the UK alone
• The construction industry spends over £200 million on landfi ll tax
each year
• 13 million tonnes of construction and demolition waste is material
that is delivered to sites but never used!
• Over 5 million tonnes of hazardous waste is produced in England
and Wales, 21% of which is produced by construction and
demolition
• Construction and demolition waste form nearly 30% of all Environment
Agency recorded fl y tipping incidents
The quantity surveyor and the construction industry 29
• In addition, around 40% of total energy consumption and greenhouse
gas emissions are directly attributable to constructing and
operating buildings.
Although high on the face of it, the true cost of waste is generally
around 20 times that of the costs due to the following:
• Purchase cost of materials
• Cost of storage, transport and disposal of waste
• Loss of income from selling salvaged materials.
The so-called waste hierarchy has been described as follows:
• Eliminate – avoid producing waste in the fi rst place
• Reduce – minimise the amount of waste you produce
• Re-use – use items as many times as possible
• Recover (recycling, composting, energy) – recycle what you can
only after you have re-used it
• Dispose – dispose of what is left in a responsible way.
The process of getting the minimum whole life cost and environmental
impact is complex, as illustrated in Figure 1.4. Each design option will
have associated impacts, costs and trade-offs, e.g. what if the budget
demands a choice between recycled bricks or passive ventilation?
-EMBODIED ENERGY
-OPERATING ENERGY
-GLOBAL WARMING IMPACT
-ATMOSPHERIC POLLUTION
-DISPOSAL POLLUTION
-AIR QUALITY
-CONSERVATION
-DURABILITY
-RECYCLABILITY
-SOCIAL AND COMMUNITY IMPACT
-POLLUTION
-RESOURCE CONSERVATION
TECHNIQUE, MATERIALS CHOICES, TECHNOLOGIES
COSTS
IMPACT
Figure 1.4 Graph showing the minimum whole life cost and environmental
impact
30 Quantity Surveyor’s Pocket Book
The solution to a complex problem will be iterative.
Generally, attention to the following issues will increase the design
costs, but not the costs of the building itself and will reduce
whole life costs:
• Short supply chains to reduce transport costs
• Exercise waste minimisation and recycling construction
• Building orientation
• Durability and quality of building components, generally chosen
to last for the appropriate refurbishment or demolition cycle
• Local sourcing of materials
• Design sensitive to local topological, climatic and community
demands
• Construction type – prefabrication, wood or concrete structures.
During procurement supply chains should be aware that components
should be chosen selectively to minimise:
• Embodied energy; energy of production and transport
• Atmospheric emissions from boilers, etc.
• Disposal to landfi ll of non-biodegradable waste
• Air quality contaminants, e.g. solvents and wood preservatives
continue to emit volatile chemicals long after construction, though
in much smaller quantities and these have been implicated in
‘sick building syndrome’
• Replacement due to poor durability
• Use of fi nite resources, or at least promote the use materials like
wood from forests which are being replenished.
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