Interdisciplinary building categorization - A method to support sustainable energy efficiency strategies in historic districts

The balance of energy conservation and building conservation must be carefully considered when developing management policies for historic districts. One possible approach is using building stock modelling. However, as state of the art models do not normally encompass aspects or values related to cultural heritage significance, new interdisciplinary categorization methods are required to facilitate a sustainable management of the built heritage. This paper presents a categorization method that has been developed as part of the European research project EFFESUS. It shows the procedural categorization of two very different historic centers in Palermo (Italy) and Visby (Sweden) respectively, and how they both can have the majority of their building stock volume represented by a limited number of categories. The novelty is that the categories allow for further typology investigations, e.g. energy modelling and vulnerability assessment, and extrapolation of the results back to district level. Aspects regarding heritage values are included by combining statistical building information and qualitative information from local conservation plans. The results are compared and discussed, highlighting methodological challenges related to urban characteristics and heritage policies. In all, the method shows to provide a supportive and flexible platform for investigations of a trade-off between improved energy efficiency on one hand and building conservation on the other.