Civil Engineering Reference
In-Depth Information
There is also a tendency to build too large. There can be no doubt about the fact
that smaller buildings use fewer resources! The same applies to energy consump-
tion in a building which is of optimal size. There is a greater efficiency co-efficient
in such a building compared with the use of heat pumps, solar panels and thick,
insulated walls in a less optimized building. This is one of the greatest challenges
for architects of the future - to make small buildings as comfortable as possible.
Reduced loss of building materials
Every material has a 'loss factor' which describes how much of a particular mate-
rial is lost during storage, transport and installation of the final product. As well
as indicating the amount of wastage the material undergoes, the loss factor gives
an idea of the amount of resources lost. For many materials, increased prefabri-
cation would decrease this loss, which would be further strengthened through an
increased standardization of products.
Loss of materials on site is approximately 10 per cent of the total waste in the
building industry. In Scandinavia in the last few years there have been a number
of large projects where the amount of material loss has been reduced by more
than 50 per cent through, amongst other things, having usefully planned site
management. Sawn off timber lengths and waste products have been separated
out and kept within the building process (Thonvald, 1994).
Within the building industry a great deal of packaging material is also used
during transport and for storage on site. Some packaging serves no greater pur-
pose than to hold the name of the firm. An important aspect of packaging is that
it should be easy to recycle, and therefore should not comprise different materi-
als such as aluminium or plastic emblems printed on cardboard.
Loss of material caused by wear and tear in the completed building will also
occur. In Sweden in 1995, the Department of the Environment estimated that the
loss of copper from roofs and pipes etc. through weathering amounts to more
than 1000 tons per year. Apart from the pollution risk, there is also a huge loss of
resources that could be recycled. Materials based on rare, non-renewable
resources should not be used in exposed parts of the building.
High durability
By producing more durable products the use of raw materials is reduced by
ensuring that materials of the same durability are used during the construction
process, therefore not sacrificing better quality components in a building when
there is decay elsewhere. If there are any materials of a lesser quality, then it is
important that they are easily replaceable while the more durable materials can
be dismantled for re-use or recycling in the case of demolition. As far as resources
are concerned, there is a clear advantage in using robust materials and allowing
buildings to last as long as possible.
