Energy and financial impact of poor air tightness in existing residential buildings

The improvement of air tightness in existing residential buildings could be triggered from the desire for better indoor comfort conditions and the expected reduction of cost for space heating. While the improvement of comfort sensation could not be easily understood from the building owner, the reduction of cost for space heating is much easier. In order to estimate the potential energy saving and the relative reduction of cost for space heating, has been calculated the annual energy saving of heating load per m³/h of infiltration for residential buildings located in various European countries. The annual reduction of cost for space heating has been estimated in absolute values (€ per m³/h) taking into account various assumptions related to the heating system and the energy source. Furthermore, it is provided a correlation between the reduction the air change rate at 50 Pa and the potential cost savings. The methodology has been implemented for estimating the potential of energy saving and the possible reduction of cost for space heating for various case studies given from existing studies.