Thermal properties of the vernacular buildings envelopes: the case of the “Sassi di Matera” and “Trulli di Alberobello

The stone and the clay are the basic elements of the existing architectural heritage in the Mediterranean area, both historical and monumental. The study cases taken into account are the "Sassi of Matera" and the "Trulli of Alberobello." The thermohygrometric performances of the "Tufo of Matera" (commonly denoted as calcarenite sandstone) and the "Stone of Fasano" (commonly denoted as calcareous stone), which are the base materials of the buildings "Sassi" and "Trulli", were quantified through measurements in situ, realized with nondestructive methodology and analyses in laboratory. The behavior of these constructions has finally been better described with dynamic simulations developed by the software EnergyPlus. This study demonstrated that the thermal mass of these structures mainly affect the indoor microclimate, stabilizing the inside temperatures and thus annulling the great thermal daily oscillations of the external temperature. The results of the measurements and numerical simulations confirmed that the seasonal thermal storage of these structures allows comfortable temperatures during the summer season, with values below 26°C, and stabilizes the indoor temperatures during the winter season, through the release of the heat stored during warm season.