A General Approach for Retrofit of Existing Buildings Towards NZEB: The Windows Retrofit Effects on Indoor Air Quality and the Use of Low Temperature District Heating

The European Union, through the Energy Performance of Building Directive (EPBD), has recently set the minimum requirements in order to reduce the energy consumption of existing buildings and achieving nearly zero energy buildings (NZEBs). In order to comply with these requirements different aspects of the building sector have to be dealt with. In the present paper two different aspects related to the energy and environmental performances of the existing building towards NZEB are analyzed: a) the use of the Smart Energy Systems with particular regard to the heat sharing systems, and b) the effect of the window retrofit on indoor air quality.