Empirical investigation of interzonal air leakage and airborne sound transmission correlation in multi-unit residential buildings

Abstract

In the context of suite compartmentalization in multi-unit residential buildings, knowing the airtightness of individual pressure boundaries (e.g. floor, corridor wall, suite wall, etc.) is imperative for the diagnosis and remediation of issues such as regulating ventilation air delivery and managing pollutant transfer. However, conventional quantification methods, such as the pressure neutralization method, are cumbersome to complete. The feasibility of an acoustic testing approach, which leverages the relationship between increased air leakage rate and decreased airborne sound transmission loss was examined. Limited studies have explored this relationship in building enclosure elements, and no attempts were made to assess the correlation in interior partitions. In-situ measurements were conducted across twelve suite partition walls from three multi-unit residential buildings to obtain experimental correlations between the two parameters. The area-normalized air leakage rate at 50 Pa (q50) varied among specimens of the same composition, demonstrating the importance of air-sealing details for the overall partition airtightness. The variation in q50 was best reflected by the area-normalized sound transmission loss at 630 Hz; a non-linear model and the inclusion of air pressure differential information also improved the models’ accuracy. While the root-mean-square error of 0.56 L/s/m2 in q50 prediction suggests this acoustic approach needs further refinement to verify compliance with increasingly stringent compartmentalization targets, the current study demonstrates the application and potential benefits of the acoustic approach in a real-world context. Further data could improve the model so that it could be suitable for screening partitions with similar construction and in pre- and post-retrofit comparisons.