TL;DR
Kneewall insulation is the thermal treatment of the short vertical walls separating finished attic rooms from unconditioned side-attic spaces, a notorious weak spot because batts stuffed in open-backed stud bays fall away and let attic air wash around them. Effective work adds an air barrier, rigid foam or sheathing, on the attic side of the insulation, seals the floor cavities running under the wall with blocking, and weatherstrips the access doors.
What it means
Kneewall insulation is the thermal treatment of the short vertical walls separating finished attic rooms from unconditioned side-attic spaces, a notorious weak spot because batts stuffed in open-backed stud bays fall away and let attic air wash around them. Effective work adds an air barrier, rigid foam or sheathing, on the attic side of the insulation, seals the floor cavities running under the wall with blocking, and weatherstrips the access doors. Energy auditors target these areas in story-and-a-half houses where bonus rooms run hot in summer and cold in winter.
Where it sits in the glossary
Kneewall insulation 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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