Optimisation of opaque components of the building envelope. Energy, economic and environmental issues

The European Directive 2002/91 will enforce the Member State to promote the implementation of new measures, instruments and calculation methodology to improve the buildings energy performances. The thermal performance and quality of the Italian residential buildings is generally poor, depending on the age of the building stock and the lack of application of the existing energy regulations. This study aims at demonstrating the global benefits of good insulated buildings envelopes. Energy benefits are easy to understand, meanwhile the economic issues are critical, since the final users see them as an additional useless extra cost for the dwelling at the purchase phase, with small attention to the future managing costs. The study demonstrates that significant economic advantages come out from high performance building envelope. The study also shows that environmental extra loads due to a bigger use of the insulation metarial is paid back in few years, with consistent social benefits if the life cycle of the building is taken into account.