Bioclimatic design of buildings considering heating requirements in Italian climatic conditions. A simplified approach

This paper presents a parametric approach to the definition of a proper building shape compared to the building heating requirement in the very first stage of the design process. A new simplified index is introduced, namely the south exposure coefficient Cfs. In fact, as far as bioclimatic architecture is concerned, the relationship between buildings and natural environment is very important both for the control of indoor comfort conditions and energy requirements. The building shape is a fundamental aspect of this relationship. Usually, in thermal behavior analysis this parameter is considered only from the point of view of compactness. This is a reductive approach, because two buildings with the same coefficient could have different shapes and so a different thermal behavior. Some aspects such as orientation, openings, exposure to atmospheric agents and natural elements must also be strictly considered. Moreover, in scientific literature no indications are given to designers who operate in mild and warm climate conditions. This is why the results of a research activity focused on heating requirements of buildings with different shapes and laid in the Italian territory are presented. Monthly calculations have been performed following the quasi-steady-state method suggested in the European standard. Outputs show that better results in the building energy performance can be achieved considering a bioclimatic (though simplified) approach since the very beginning.