Seismic and energy refurbishment of residential built heritage in Mediterranean climate

The built heritage tells of the close relationship between man and environmental resources; this has defined the image of our historic cities in the material and formal aspects. According to ISTAT data, the residential historic buildings (built before 1919) account for 19.2% of the Italian built heritage. Considering the masonry buildings, this percentage increases to 61.5%, if we think that this constructive type had also been used up to the 1950s. This heritage must meet two needs of contemporary society: environmental sustainability, especially in terms of energy-consumption reduction, and the mitigation of seismic risk. For historical architecture, we must also add the cultural setting, to be considered in order to preserve the testimonial values for future generations. The paper presents the study of a historic building in Catania, a city in highly seismic area and in the Mediterranean climate. The case study belongs to a widespread constructive type in the urban fabric of the nineteenth century. In this research, we evaluate the reduction of energy demand through measures in respect of the cultural setting, referring to the national legislation in force. We also propose to identify the possible labilities inherent in geometric configurations, building techniques and existing decays that may weaken the structural performance in case of an earthquake; this being in relation to the Italian Guidelines 2011 for assessing and reducing the seismic risk of cultural heritage. In this way, it will be possible to define guidelines for energy refurbishment and seismic improvement that are reasoned and compatible with the "corpus" of the traditional building, without altering historic and cultural settings.