Author: Graham Finch, Dipl.T., M.A.Sc., P.Eng.

An airtight building enclosure is an important part of a modern building. Good airtightness can increase energy efficiency, improve durability, and allow greater control over occupant comfort and indoor air quality. Airtightness is achieved with an effective air barrier system that is carefully designed and detailed and then built and commissioned in the field. An effective air barrier consists of a continuous system of materials (building wraps, membranes, etc.), components (doors, windows, etc.) and accessories (tapes, sealants, gaskets, etc.). These air barrier elements must be individually airtight and airtight when used together.