TL;DR
Draftstopping is the subdivision of large concealed air spaces in a building, the cavity between a dropped ceiling and the floor above, or an open floor-truss bay, with sheets of drywall, plywood, or OSB so fire and smoke cannot race horizontally through the hidden volume. The IRC caps these concealed spaces at 1,000 square feet in homes, and the requirement typically surfaces in basements with suspended ceilings and in townhouse construction.
What it means
Draftstopping is the subdivision of large concealed air spaces in a building, the cavity between a dropped ceiling and the floor above, or an open floor-truss bay, with sheets of drywall, plywood, or OSB so fire and smoke cannot race horizontally through the hidden volume. The IRC caps these concealed spaces at 1,000 square feet in homes, and the requirement typically surfaces in basements with suspended ceilings and in townhouse construction. It differs from fireblocking, which seals the small vertical gaps and penetrations; this measure partitions big horizontal voids, and inspectors check both before insulation hides the evidence.
Where it sits in the glossary
Draftstopping 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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