An empirical approach to improving preconstruction airtightness estimates in light framed, detached homes in Canada

Abstract

In order to estimate preconstruction airtightness in conventionally constructed homes, a local blower door testing population of 2297 homes was examined. Three builder-specific, geometric-based, temporally independent, multiple linear regression models were developed. Some of these builder-specific models explained over 58% (R = 0.79, p ≪ 0.001) of whole building airtightness. A five variable, geometrically based model which controlled for handicraft explained up to 74% (R = 0.87, p ≪ 0.001) of the whole building airtightness. The regression-based analyses on the local population suggested that air leakage is prominent through two building details: the floor-to-wall, and at the window-to-wall assemblies. While many comparable studies formulate airtightness models as a method to estimate post construction homes, this study demonstrated that preconstruction airtightness could be estimated with a temporally independent, builder specific, and geometrically-based method. Furthermore, this regression approach suggests that the methodology presented could be utilised as a design tool by members of the construction industry under a strict set of limitations.