Civil Engineering Reference
In-Depth Information
Introducing the measurement of energy performance as a
design parameter early on in the design process will lead to
a good efficiency rating and define what construction, build-
ing form and modern methods of construction are suitable
solutions.
4.3.7
Measurement frameworks
In the previous section, we discussed some clear-cut ways to
measure sustainability. However, in recent years a plethora of
assessment methods have begun to dominate the market in dif-
ferent regions of the world. The assessment methods all have a
similar structure, that in essence establishes a set of appropriate
categories and assigns points to each category. Each category
has a weighting which is a subjective measure of how important
that category is deemed to be. The weightings are used to prod-
uce a final value (usually a percentage) which represents how
well a design or building matches the criteria. The most used
and widely accepted methods around the world are BREEAM
(UK), CEEQUAL (UK), LEED (US) involved and Green Star
(Australia) and
Table 4.2
outlines the categories involved and
provides example weightings used in each method.
4.3.6
Key Performance Indicators (KPI)
Since the late 1990s, the construction industry has been bench-
marking environmental performance of projects with Key
Performance Indicators. Any project over the value of £100k is
measured using KPIs which are monitored through the measure-
ment of the reduction of waste removed from site, energy and
water used during the construction process as shown in the 2009
Construction Statistics Annual
(Office for National Statistics,
2009, Table 16.6) and reproduced in
Table 4.1
. This has led to the
introduction of Site Waste Management Plans, Environmental
Impact Assessments and the Considerate Contractors Scheme.
More recently in 2005 the UK Government's Sustainable
Development Strategy launched 'Securing the Future' (Defra,
2005) which asks the construction industry for developments
that deliver sustainable, towards-carbon-zero and zero-waste
solutions. To achieve these targets we must adopt them at the
beginning of the design process so they become a part of the
project itself and build in cost savings.
4.3.8
Building Research Establishment Environmental
Assessment Methods (BREEAM)
BREEAM is the commonly used assessment method for build-
ings in the UK and rates buildings from Outstanding to a Pass.
In the 1990s, the Building Research Establishment (BRE)
established an Environmental Assessment Method which was
to be used voluntarily on projects to measure sustainability in
the built environment. It initially focused on offices, schools
Performance
KPI
Measure
2005
2006
2007
2008
2009
Impact on the environment
- product
% scoring 8/10 or better
53%
54%
51%
55%
64%
- construction process
% scoring 8/10 or better
44%
45%
44%
48%
49%
Energy use (designed) - product
Median energy use kg CO
2
/
100m
2
gross floor area
4291
3729
3775
4474
4539
Energy use - construction process
Median energy use kg CO
2
/
£100k project value
293
293
273
192
241
Mains water use (designed) - product
2
Median water use m
3
∕ 100m
2
gross floor area
53.2
52.0
90.4
80.0
49.5
Mains water use - construction process
Median water use m
3
∕ £100k
project value
8.2
8.9
8.2
7.1
6.3
Waste - construction process
Median waste removed from
site m
3
/
£100k project value
41.6
37.0
39.1
36.9
36.6
Commercial vehicle movements -
construction process
Median movements onto site ∕
£100k project value
29.4
30.4
29.4
26.5
28.3
Impact on biodiversity
- product
% scoring 8/10 or better
33%
36%
34%
35%
31%
- construction process
% scoring 8/10 or better
45%
48%
46%
49%
47%
Area of habitat - created/retained - product
% reporting no change or an
increase in area of habitat
76%
83%
78%
80%
82%
Whole life performance - product
% scoring 8/10 or better
41%
41%
39%
35%
44%
1 KPI data for earlier years can be found in previous editions of Construction
Statistics Annual.
2 Limited data use with caution.
Note
: Sample sizes and distribution of data between construction sectors for some Environment KPIs have not yet stabilised.
Table 4.1
Summary of industry performance from 2005 to 2009 - Environment KPIs (
Construction Statistics Annual
, 2009) © Crown copyright 2009
