Social housing as an open issue of energy consumption in the building sector in Europe: a case study in Berlin

The decarbonization goal by 2050, as set by Directive 844/2018, is an ambitious objective that requires a big effort. The strategy to act on the building sector includes the construction of new highly efficient buildings and the energy refurbishment of the existing ones. This study focuses on the renovation of social housing buildings, which are a wide component of the existing building stock, and in most cases, present poor energy performances. The investigation focuses on the role that social housing plays in the European building stock, from an energy point of view, and through significant examples, review the strategies adopted to improve their energy performances. A significant case study in Berlin, representative of both German and even European social housing, was investigated by selecting energy efficiency measures to improve its performance. In a final configuration that combines different energy efficiency measures, a heating thermal energy saving of 88% was obtained. The study includes a technical economic analysis of the proposed energy efficiency interventions and shows how some of them are not economically convenient without governmental incentives.