Air will leak through a building envelope that is not well sealed. This leakage of air decreases the comfort of a residenceby allowing moisture, cold drafts, and unwanted noise to enter, and air leakage can account for up to 40% of the energyused for heating and cooling in a typical residence. With nearly a mile of exterior joints that can leak air in a typical residence,knowing which joints leak the largest quantity of air allows for the most strategic placement of sealant. This twopartpaper describes an extensive investigation to quantify the leakage characteristics of various types of joints and openingsin a residential structure. All-in-all, 17 different joints/openings were characterized through both laboratory and real-housemeasurements using fan pressurization. Part 1 presents the methods and results associated with the air leakage of the individualjoints/openings. Part 2 adapts these individual results to the whole house, including an examination of the joint leakageinterdependence in the wall cavity.

Presented at Thermal Performance of Exterior Envelopes of Whole Buildings XII, December 2013