Comparing indoor performances of a building equipped with four different roof configurations in 65 Italian sites

Despite the increasing concern of institutions and technical organizations toward the improvement of the building energy (and, therefore, environmental) efficiency, the main goal of technicians should be also devoted toward the levels of internal thermal comfort that buildings are able to realize. As that, the relationships between energy performances and comfort conditions provided by the enclosures are of paramount importance in guiding designers in their work. In this paper, the influence of diverse roof construction typologies on energy and indoor performance of buildings has been investigated, in different Italian sites during heating and cooling seasons. In addition, it must be properly considered that buildings operate in given climate and weather contexts that deeply affect their performances. Hence, for taking into account the different weather conditions of each site, a new parameter has been used, that is the "Climatic Severity Index" corresponding to a value of magnitude of a climatic vector less a constant value, recently released by an Italian technical standard. The actions for improving the energy efficiency sometimes lead to a reduction of indoor comfort, therefore, not always easily applicable.