Energy retrofitting of historical buildings in mediterranean areas

The most suitable intervention for energy rehabilitation of historical buildings has to reach both the goal of the optimization of the energy saving and the preservation of the original characteristics of the building. The possibility of restoring these historic buildings, re-utilizing them for a different purpose, and requalifying them with a view to reducing energy consumption, is an interesting issue for the city of Catania (Italy), if we consider that the abandoned buildings in the city centre currently represent a significant part of the architectural heritage. The method of intervention proposed to give abandoned historic buildings a new energy-saving efficiency was applied to a building in the Old Town of Catania which had served until the early nineteen-eighties as a foundry for the realization of works in cast iron. The interventions to be carried out on the building envelope are designed to meet the requirements connected with the new destination of the building. The strategies employed aim to adopt technological solutions in perfect harmony with the new requirements and to regulate the thermo-hygrometric conditions of the elements comprising the outer walls in order to respect the transmittance limits established by the current energy-saving laws. The final result of the study aims to supply indications which, taking into account the individual characteristics of the different cases studied, may be repeated within the same context, both at a local district level and at that of the entire historic centre, whenever a common matrix may be discovered for the environmental characteristics, the construction techniques and the materials used.