Stone building envelopes performance qualities: the “Sassi di Matera” (Italy)

As a constantly important feature of the architecture, in both formal and technical-building aspects, with which it has established a biunique relation, the stone has always been able to guarantee performance qualities suitable for living conditions in each single century. In time, the technological process, on one hand, and the complexity of anthropical activities, on the other, have caused the breaking of this relation, generating a more and more increasing demand for performances. This necessity, supported by an increasing complexity/stratification of building envelope and also by the use of materials no more directly available near the building area, has caused a change of the equilibrium between man and environment, consolidated in time. The study faces the recovery theme of the historical and monumental building, characterized by an “imposing” envelope, in which all the performance are entrusted at the same component and/or material (the stone masonry), pointing out the formal aspects, strongly correlated with static and technological ones. The complexity of this approach, also referred to restraints imposed by the built heritage, do not allow a wide range of solutions, and fix the necessity to value the envelope characteristic restoration and implements a possibility to developed the building performance. This is reversible and compatible choice, fully respectful of environmental characteristics. The aim of the research is to verify, by means of a series of tests for monitoring the “comfort indoor”, how it is possible to obtain performance requirements corresponding to quality standards that the residence requires, even in a particularly important architectural context, as the ancient “Sassi” of Matera.