Sustainability assessment of historic buildings: lesson learnt from an Italian case study through LEED® rating system

Environmental certification is a key issue for improving energy efficiency, minimizing energy consumption and allowing greater transparency on energy uses in buildings. If sustainability of the building process is an already consolidated issue for new constructions, as well as for existing buildings, for traditional and historic buildings a dedicated consideration still must be carried out, due to the major complexity of the variables to be taken into account. This paper deals with the criticality of applying LEED (R) Italia rating systems for New Construction and Major Renovation to the case study of an ancient stable located in correspondence to a Middle Age fortress in Perugia, Italy. This gap analysis process shows the weakness of existing tools when applied to the historical context, by highlighting the need of a new assessment framework in case of restoration and preservation processes. GBC Historic Building (TM), a new rating system that GBC Italia is now developing, offers the opportunity to combine framework and criteria of the International LEED (R) standards and the specific knowledge of the restoration and preservation theory and practice. The case study highlights possible modifications and integrations of the existing LEED (R)/GBC topics, with the ultimate purpose of bridging the gap between energy efficiency, environmental sustainability and cultural heritage preservation.