An air barrier blocks airflow through the building envelope. It reduces heat loss by preventing air from passing in and out through the envelope and protects the insulation and structure from moisture damage. The air barrier, when located on the exterior, may also act as part of the drainage plane. Standard building materials, such as exterior shea [..]

A material or structural element that inhibits air flow into and out of a building's envelope or shell. Often it allows water to diffuse through it. See also Vapor Barrier.

An air-infiltration barrier or house wrap that can be used to protect a storage area in the attic from moisture and dust.

The element in an assembly designed and constructed to control air leakage between a conditioned space and an unconditioned space.

Building assembly components that work as a system to restrict air flow through the building envelope. Air barriers may or may not act as a vapor barrier. The air barrier can be on the exterior, the i [..]

  The barrier that prevents infiltration of outdoor air into the conditioned space and exfiltration of indoor air to the outside. Also known as “pressure boundary”, it should be continuous and aligned [..]

Any part of the building shell that offers resistance to air leakage between indoors and outdoors. Air barriers can be composed of many combinations of materials including properly installed drywall, [..]