TL;DR
Blown-in fiberglass is loose-fill insulation of fine glass fibers blown pneumatically into attics and closed wall cavities, delivering about R-2.2 to R-2.9 per inch in open attic applications and more when dense-packed. It does not settle appreciably, resists moisture and mold inherently, and is the lightest option for ceilings with fragile drywall.
What it means
Blown-in fiberglass is loose-fill insulation of fine glass fibers blown pneumatically into attics and closed wall cavities, delivering about R-2.2 to R-2.9 per inch in open attic applications and more when dense-packed. It does not settle appreciably, resists moisture and mold inherently, and is the lightest option for ceilings with fragile drywall. Its weakness is air permeability, as loose depths lose effective R-value when cold attic air circulates through the top layer, an effect reduced by deeper installs and air sealing first. Bags-per-square-foot coverage charts on the package are the verification tool at final inspection.
Where it sits in the glossary
Blown-in fiberglass 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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