Are the best available technologies the only viable for energy interventions in historical buildings?

Worth aged buildings represent among the existing buildings a special case when it comes to their energyrefurbishment. Unfortunately, the available technologies for building components characterized by highlevel of thermal performances show, not rarely, a limited compatibility with the architectural integrityof the building. In other words, the so-called Best Available Technologies, which are effectively adoptedto optimize the building energy performances, in case of buildings to which a certain artistic, historicand/or architectural merit is recognized, i.e. heritage houses, might determine such kind of conflicts. Thissituation may lead to the selection of “non-invasive” but less performing building and plant elements.To check the effectiveness of these less performing technologies, we investigated the energy perfor-mance of two different refurbishment configurations of the building envelope of a heritage house: a “BestAvailable Technology” scenario, in which interventions assumed consist of using the Best Available Tech-nology for energy saving; and an “Allowed Best Technology” scenario, in which interventions assumedconsist of using technologies that, although not the best available ones, are anyway “allowable” accordingto the cultural heritage preservation requisites and rules. A cost-based comparison between these twoconfigurations was also made. Results of this comparative analysis are reported here.