TL;DR
Fireblocking is the solid material — 2x lumber, plywood, gypsum board, or unfaced mineral wool — installed inside concealed wall and floor cavities to cut off the hidden channels through which flames and hot gases race vertically and horizontally inside a frame building. The IRC requires it at ceiling and floor levels, every 10 feet horizontally, at soffit connections, and around stair stringers and chases.
What it means
Fireblocking is the solid material — 2x lumber, plywood, gypsum board, or unfaced mineral wool — installed inside concealed wall and floor cavities to cut off the hidden channels through which flames and hot gases race vertically and horizontally inside a frame building. The IRC requires it at ceiling and floor levels, every 10 feet horizontally, at soffit connections, and around stair stringers and chases. It differs from firestopping, which seals penetrations in rated assemblies; fireblocking compartmentalizes ordinary wood framing.
Where it sits in the glossary
Fireblocking 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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