Search

Abstract Infiltration plays a relevant role regarding the energy performance of buildings. Many European countries have already established standards which aim to limit the energy waste through the envelope following the European Energy Performance of Buildings Directive guidelines. However, in Mediterranean countries there is still a lack of knowledge in this field. An extensive study has been carried out in order to characterize the air leakage through the envelope of the existing housing stock in the Continental climate area of Spain. Results of 129 dwellings tested, including different typologies and periods of construction, are shown. Blower door tests were performed, and thermal imaging was used to locate leakage paths. Single-family dwellings were found to be more airtight than apartments, given that the mean air permeability rate at 50 Pa (q 50) was 5.4 m3/h·m2 and 6.8 m3/h·m2 respectively. The mean air change rate at 50 Pa (n 50) was 6.1 h−1 for single-family dwellings and 7.1 h−1 for multi-family housing. Nevertheless, great dispersion of results and extreme values were found. In addition, the influence of several construction characteristics on permeability results was assessed. Highlights • Pressurization tests were performed in 129 dwellings in the Spanish Continental area. • The mean ACH50 was 7.1 h−1 for apartments and 6.1 h−1 for single-family dwellings. • No relationship was found between construction features and permeability results. • Leakage places were located in windows, shutters, ducts and construction joints. [ABSTRACT FROM AUTHOR]

People spend most of their time indoors in residential buildings; thus, maintaining good indoor air quality (IAQ) is essential. It is necessary to provide a suitable ventilation rate in these spaces (low-density occupation) taking into account that materials (finishes and furnishing) are one of the main sources of indoor pollution. For that purpose, this research, based on both the National Research Council (NRC) database and a specific case study, followed a method that consisted of the identification of indoor pollution sources, evaluation of the emission factor and characterization of the IAQ. It is intended to show the influence of materials (quantity, type and age), loading ratio and pollution concentration threshold in the calculation of a ventilation rate which guarantees a good IAQ. This study also reflects the need to bring together an overall pollution concentration threshold of TVOC, below which a safe level of exposure to indoor pollution is recognized. [ABSTRACT FROM AUTHOR]

Highlights: [•] Convective strengths prevail with respect to the direction imposed on the air inlet. [•] Changes in age of the air depend on the flow pattern established by the temperatures. [•] The interchange of the energy causes the room average age not to change significantly. [•] CFD tools are very useful for the study of the airflows in rooms. [ABSTRACT FROM AUTHOR]