Heritage and sustainability. From general issues to concrete applications. A proposal for the assessment for the historic buildings

The risk of losing tangible heritage was becoming a real scientific issue, gathering contributions from different cultures. The Italian model stemmed from the belief that risk was fundamentally a combination of the vulnerability of cultural heritage and the various hazards of the territory in which these objects exist, with a focus on the physical, biological and chemical characteristics of the environment, as well as the material and construction features of the heritage. The article proposes a way to estimate sustainability in relation to the risk of loss of architectural heritage. In this perspective, sustainability and risk are seen as two sides of the same coin: the higher the estimated risk, the lower the sustainability results (and vice versa). Sustainability is not always immediately expressible by reference to the individual parameters of the vulnerability of the spatial hazard. However, the risk calculation allowed by the Italia Risk Map is based on data and produces reference indices that, suitably processed, could also express the level of sustainability of a historic building or restoration work.