Improved sealing of attached garages reduces infiltration of polluted air into adjoining dwelling spaces

A field study was conducted in Ottawa, Canada involving 31 homes with attached garages to evaluate the effectiveness of two interventions aimed at reducing the infiltration of pollutants from attached garages into adjoining living spaces. This paper describes the results of the second intervention where the airtightness of the interface between the home and garage was improved. Before and after the sealing intervention the air exchange rates (AERs), airtightness (ACH₅₀), and effective leakage areas (ELA₁₀) were measured for both the home and garage along with the garage-to-home inter-zonal air flows. Following the intervention, the garage-to-home inter-zonal air flow was reduced by 48.8% and the airtightness of the home and garage improved by 5.3% and 9.2% respectively. This study demonstrates that improved sealing of the garage building envelope is a practical, low cost, and effective intervention to reduce air infiltration from attached garages into adjoining living spaces.