Active House in Mediterranean Country: First assessment on energy needs and thermal comfort

The last Century witnessed an increasing awareness about energy efficiency in the construction sector, seen as the only possible solution to smooth the negative effects of buildings on the environment. Therefore energy efficient design and envelope innovation have been pushed, decreasing the thermal dispersions through enclosures and minimizing flows exchange. The adiabatic concept of dwellings, however, brings to a criticism: increasing internal gains and the risk of overheating, especially in warm climate. The analysis proposed aims to understand the robustness of the design choices in the Mediterranean climate, defining the resilience associated to different architectural and technical solutions. A model of Active house is taken as case-study and different technological scenarios are created. The results are compared both on the energy needs and the indoor thermal comfort provided. The results show that, to increase the resilience of buildings in Mediterranean climates, it is important to act on the exchange flows with the outdoor, integrate a proper shading system (or closing the south façade and opening the northern one) and avoid over insulated skins, which easily bring to overheating. This work shows the importance of coupling comfort and energy consumption in buildings performances evaluation to achieve a reliable and robust design. Keywords: active house, warm climate, overheating, energy efficiency, thermal comfort