Energy Consumption and Indoor Comfort in Historic Refurbished and Non-refurbished Buildings in South Tyrol: An Open Database

To achieve the EU energy-saving targets, renovation of existing buildings requires particular attention. In total, historic buildings amount to one fourth of Europe's building stock. Also, in the Province of Bolzano (Northern Italy), 30% of the building stock was built before the end of World War II-in some municipalities even around 60%. Therefore, energy refurbishment of this sector represents an opportunity to reduce CO2 emissions and to provide comfortable living space using existing resources and preserving cultural and social values. In this work, we collect information on the energy behaviour of historic buildings in South Tyrol, analyzing some representative "best practices". "Best practices" have been selected in accordance with the local heritage authority, and have been defined as successfully retrofitted buildings that satisfy both energy and heritage conservation aspects. The aim is to show that retrofitting historic buildings is feasible and also can achieve high levels of comfort and low-energy consumption, while keeping our cultural heritage alive and exploiting existing resources. The collected information is based on interviews and on-site visits that includes: the use of the building, the building geometry, the thermal envelope, the heating system, the use of renewable energy sources, the energy consumption and the perceived comfort inside the building. All this information is made available in an open database that enables building owners and planners to estimate the energy consumption of their building, to learn the most frequently used retrofit solutions, and to forecast the possible energy savings and the improvement of comfort if the building is refurbished. The database represents a knowledge source and an access to trustworthy information for all stakeholders, going beyond the state of the art certainly in the respect to architectural quality of deep renovations.