A methodological proposal for compatibility interventions of energy efficiency improvement in historical buildings: the case study of Palazzo d’Accursio in Bologna

The definition of intervention strategies for the restoration of the historical buildings requires a very different approach compared to that of traditional buildings, in particular with regard to the objectives of comfort and energy savings that can not be separated from the peculiarities of preservation of the historic monumental good. The objective of this work is to define an approach for the analysis of historical buildings that can extend the traditional analysis of a historico-evolutionary and architectural support of the restoration project, and to suggest changes to energy surveys normally applied to existing buildings. The proposed methodology is divided in several stages: firstly an accurate integrated interpretation of the building, which covers investigations and documentary archive on the history of the building, the stratifications plant, dimensional and geometric reliefs, energy audit, observations of the architectural texture. The second step is the evaluation of the simplifications needed for a proper mixing of different layers above examined and the definition of an appropriate representations of synthesis. Finally, from the hypothesis of intended use and the analysis of actual constraints, we select the proposals of intervention that take greater account of the contemporaneity of the different bodies. This methodology was developed from experimental surveys conducted on one of the buildings more complex and representative of the city of Bologna, Palazzo Co-munale d’Accursio, where the extent of this architectural complex, the evolution over the centuries for aggregation of blocks, and the monumental importance in the differentiation and centrality of the intended use present, make this case study very significant