TL;DR
An air barrier is the continuous layer of materials in a building enclosure, such as sealed sheathing, house wrap, membranes, gaskets, and caulked joints, that stops uncontrolled airflow between inside and outside. It is distinct from insulation, which slows heat but does not stop air, and the two must touch each other to work as designed.
What it means
An air barrier is the continuous layer of materials in a building enclosure, such as sealed sheathing, house wrap, membranes, gaskets, and caulked joints, that stops uncontrolled airflow between inside and outside. It is distinct from insulation, which slows heat but does not stop air, and the two must touch each other to work as designed. The IECC requires a continuous one in new construction and verifies it with a blower door test. Gaps at rim joists, top plates, and penetrations are where most assemblies leak and where energy retrofits focus.
Where it sits in the glossary
Air barrier is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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