Environmental and health related criteria for buildings - ANEC

IBO - Environmental and Health related Criteria for Buildings
not be the case for similar products but may be useful for comparisons of different product
families (ANEC, 2009-1).
The LCA of the building structure can be improved by changing the material composition.
The results of IMPRO (2008) showed that significant environmental improvements could be
expected only when “conventional” products like concrete, reinforced concrete, bricks were
substituted by wood products. Precondition for this finding is that the wood is taken from a
forest under sustainable management. Another very effective improvement option is to
replace cement by granulated slag.
Exchange of materials is very often the first improvement option designers think of in regard
to the building structure. But as one can easily comprehend without carrying out an LCA, the
environmental impacts will also diminish if the amount of used material is reduced. This can
for instance be done by abstaining from some construction elements or – more easily – by
increasing the compactness of the building. The latter is illustrated by the following example
of a simplified model of a single-family house.
We consider a bungalow with the dimensions 12 x 10 x 3 meters, resulting in a gross floor
area of 120 m 2 (“GFA”) and a total amount of 372 m 2 building envelope (“BE”). The building
shall have no interior walls.
If this bungalow is built with conventional materials, the LCA-scores 54 shall be 72 per m 2 BE
and 223 per m 2 GFA.
In the first step we optimize the materials and thus we achieve an LCA-score of 54 per m 2 BE
and of 166 per m 2 GFA.
Finally we consider a building with exactly the same gross floor area, but now the building
should be a 2-storey-building with the dimensions 6 x 10 x 6. This leads to 276 m 2 total area
of building envelope.
If this building is built with the same conventional materials as the bungalow, the LCA-score
per m 2 BE will be again 72, but the LCA-score per m 2 GFA is now 166.
This example shall visualise that changing the compactness of the building leads to the same
environmental improvement as exchanging the materials. This result could have been
predicted without carrying out an LCA of course. Thus the compactness of the building could
also be a good first proxy indicator for the environmental performance of the building.
54 OI3-indicator; LCA-indicator used in Austria; detailed understanding of the indicator is not necessary to
understand the example.
Final Report 89 31 03 2011