London Wider Waste Strategy - London - Greater London Authority

y volume) and furniture (17%) as the most significant arisings. This is due to the fact
that BRE carried out pre-demolition audits and therefore internal elements of the
buildings such as furniture were also included. The results of the BRE audit results are
presented in Table 5.4.
Table 5.4: % Composition of demolition waste by volume – SMARTWaste case
studies (from BRE).
Metal Plastic Concrete Timber Miscellaneous Ceramics Furniture Electrical
Goods
1.4 1.3 52.6 3.4 1.8 22.5 16.6 0.3
Source: BRE
5.20. With regard to construction wastes, the Hurley and BRE studies again report
separately by mass and volume. Both reports identify the largest waste stream as
packaging (26% and 34% respectively). There was then some similarity with Hurley
having timber at 19% (by mass) and BRE at 13% (by volume). Both have a
miscellaneous category of 14%, whilst Hurley has plastic at 13% and BRE at 5%, and
Hurley has plaster and cement at 3% whilst BRE has 14%. Hurley identifies inert at
11% (by mass) whilst BRE has it at 3% (by volume).
5.21. The results from these surveys suggest that there is a significant difference in the
composition between (a) demolition and construction wastes, particularly with regard to
the proportion of inert and non-inert wastes and (b) construction wastes depending on
the stage of the project development. The main difference between the construction
and demolition waste profiles is illustrated in Table 5.5 and suggests that a significant
difference exists between these two waste streams that are usually aggregated for data
recording and reporting purposes.
Table 5.5: Difference in the composition between demolition and construction
wastes with regard to inert and non-inert wastes
Demolition
Construction
Mass Study Volume Study
21% Non-Inert 24% Non-Inert
79% Inert 76% Inert
77% Non-Inert 78% Non-Inert
23% Inert 22% Inert
5.22. Generally the limited data available on construction and demolition waste composition
in the UK illustrates that whilst there is some level of commonality between the studies,
there are also some quite significant differences in the composition of arisings. This is
not surprising since the composition of materials arising from demolition and
construction activities varies according to the nature of the activity, building fabric, the
type of construction and the stage of the development programme. Furthermore, some
sites will require significant amounts of earthworks and may hence give rise to
excavation wastes which may be relatively small or non-existent on other sites. Finally,
of course, the above studies do not necessarily apply to London and hence it should not
be assumed that this composition can be simply applied to the total arisings to give a
breakdown into individual waste streams.
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