Air-Sealing Tips for Efficiency That Lasts // Part 2: Continuous Means Continuous
This online-only article is a supplement to the Summer 2017 print edition of Home Energy Magazine.
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BY 475 High Performance Building Supply Team
This is part 2 of a series that describes how to air seal the most difficult parts of buildings. Chris Corson, of EcoCor High Performance Buildings, likes to say that when you’re thinking about an air barrier, “continuous means continuous” —and that means no gaps, with no exceptions. The air barrier must be continuous to be effective, and continuity should be simple—it’s best to stay out of its way. Keep the red-line exercise in mind, and the fewer transitions, the better (see part 1 of this series, “Start on the Drawing Board,”). Even in difficult areas like window bucks, floor and roof joists, and stud bays, a continuous air barrier is indispensable for ensuring building performance, because a small gap in airtightness amounts to a large hole in the building assembly. Gaps, at best, cause drafts and reduce the effectiveness of insulation. At worst, gaps allow moisture loading of the assembly, which increases the possibility of mold and rot—leading to health risks and decreasing the building’s structural integrity.