TL;DR
An air infiltration rating is the measured leakage of a window or door assembly, expressed in cubic feet of air per minute per square foot of frame area (cfm/ft²) under standardized pressure testing. NFRC labels report it as an optional line, and lower is tighter: quality units test at 0.1 to 0.3, while building codes generally cap windows at 0.3 per AAMA/WDMA/CSA 101.
What it means
An air infiltration rating is the measured leakage of a window or door assembly, expressed in cubic feet of air per minute per square foot of frame area (cfm/ft²) under standardized pressure testing. NFRC labels report it as an optional line, and lower is tighter: quality units test at 0.1 to 0.3, while building codes generally cap windows at 0.3 per AAMA/WDMA/CSA 101. Unlike U-factor it captures drafts rather than conduction, so it predicts comfort near the unit on windy days. Casements usually outperform sliders because their sash compresses against the seal.
Where it sits in the glossary
Air infiltration rating 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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