Preliminary analysis results of Spanish residential air leakage database

The air leakage impact on energy performance in buildings has already been broadly studied in USA, Canada and most European countries. However, there is a lack of knowledge in Mediterranean countries regarding airtightness. An extensive study has been carried out in order to characterize the envelope of the existing housing stock in Spain. Preliminary results of more than 401 dwellings tested are shown. The sample includes different typologies, year of construction and climate zones. Blower door tests were performed and thermal imaging was used to locate leakage paths.   
Results indicate that the mean air change rate at 50 Pa of the whole sample was 7.52 h-1 and the mean air permability rate was 5.91 m3/h·m2. Different parameters were statistically analysed. Climate zone was found to have a great impact on airtightness. Other parameters such as typology, retrofitting intervention, heating and refrigerating systems, construction technology or the position of the rolling shutters were also analysed. Regarding the year of construction, unlike the trend in other European countries, it is not clear that Spanish recent dwellings have a better performance of the envelope than the old ones.