TL;DR
Open-cell spray foam is the field-applied, low-density form of sprayed polyurethane, mixed at the gun from two components and expanded in place to insulate and air-seal in a single pass. Crews apply it to attic rooflines, rim joists, and wall cavities, where its flexibility tolerates framing movement without cracking; most formulations require an ignition barrier or thermal barrier per code.
What it means
Open-cell spray foam is the field-applied, low-density form of sprayed polyurethane, mixed at the gun from two components and expanded in place to insulate and air-seal in a single pass. Crews apply it to attic rooflines, rim joists, and wall cavities, where its flexibility tolerates framing movement without cracking; most formulations require an ignition barrier or thermal barrier per code. In cold climates it can let moisture reach the roof deck, so climate-zone vapor control guides where it is appropriate.
Where it sits in the glossary
Open-cell spray foam 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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