Facade / Continuous air-leakage control
Air barrier
/ɛər ˈbær.i.ər/noun
From Greek aēr, “air,” and Old French barriere, “obstruction.”
Definition
A continuous layer of materials, tapes, and sealed joints that stops uncontrolled air from leaking into or out of a building.
Fig. 93 — Air barrier: schematic studyNOT TO SCALE
Illustrative study — Air barrier · AI-generatedSAMPLE IMAGE
Photo study — Air barrier · AI-generated00:06
Structural & construction notes
Air leaks carry far more moisture into walls than vapor diffusion does. The barrier must be continuous across walls, roof, foundation, and every opening, and is often checked with a blower-door test.
An educational reference. Project-specific design requires professional guidance.