TL;DR
Duct liner is fiberglass insulation with a durable coated face that is glued and pinned to the inside of sheet-metal ducts, providing thermal insulation and — its main selling point — sound absorption that quiets blower noise. Typical thicknesses are 1/2 to 2 inches, and the airstream surface must meet erosion and mold-resistance ratings under UL 181 and ASTM C1071.
What it means
Duct liner is fiberglass insulation with a durable coated face that is glued and pinned to the inside of sheet-metal ducts, providing thermal insulation and — its main selling point — sound absorption that quiets blower noise. Typical thicknesses are 1/2 to 2 inches, and the airstream surface must meet erosion and mold-resistance ratings under UL 181 and ASTM C1071. Old, deteriorated liner that sheds fibers into supply air is a common reason to replace ducts during renovations.
Where it sits in the glossary
Duct liner 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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