Air Barrier Systems: Your Guide to Optimal Performance

July 30, 2011
Publication: Building Design + Construction v 52 n 7 p 26-29
Author(s): Sean Obrien Waite, Michael B.

Abstract: Expert advice on how to control wasteful air leakage in the building envelope. The basic function of an air barrier system is to prevent uncontrolled air leakage through the building enclosure. An air barrier must be a complete system of materials and components that work together to provide a continuous barrier to air flow. Even small discontinuities in an air barrier can significantly reduce its performance. Air barriers must be relatively rigid or have solid backing capable of resisting moderate to high pressures caused by wind, stack effect, or mechanical pressurization of a building. Unfortunately, the air barrier "system" concept is often ignored or not considered early enough in design. This article discusses performance criteria for air barrier systems and offers solutions to common problems found in air barrier specifications. AIR BARRIER OR VAPOR RETARDER? Appreciating the difference between air barriers and vapor retarders can be a stumbling block for Building Teams, especially now that many air barriers are also vapor retarders