Energy, comfort and environmental assessment of different building envelope techniques in a Mediterranean climate with a hot dry summer

The EU regulations on energy saving have been implemented in Italy with the adoption of the North-European super-insulated model that led to the construction of buildings not much related to their climatic context. The European Directives 2010/31/EU and 2012/27/EU highlighted the importance to consider the specific climate but the development of a technical culture suitable for a temperate climate stillremains an open question. The aim of the paper is to quantify the effect on energy consumptions, comfort levels, environmental sustainability of the adoption of 3 energy efficient envelopes recently introduced in Mediterranean area and characterized by different thermal inertia (masonry, wood–cement, wood). In order to achieve this goal, a multidisciplinary approach was adopted involving: the study of the energy performance in winter and summer using analytical models both in semi-stationary and dynamic conditions (Termo and EnergyPlus programs) and the detailed analysis of thermal bridges (Therm software); the analysis of the annual comfort through dynamic analysis with Fanger’s PMV and adaptive comfort models; the quantification of environmental–economic impacts through LCA analysis (SimaPro software) with Eco-indicator 99, CED, EPS 2000 and IPCC 2001 GWP methods and LCC considering financial and environmental costs. The results made it possible to stress the differences between the various adopted methods and demonstrate that in such energy efficient envelopes the thermal mass has low influence on energy saving while it has a great effect on comfort levels and environmental burdens, with a conflicting incidence on these two aspects.