TL;DR
Chalking is the powdery white residue that forms on weathered paint and siding as ultraviolet light breaks down the coating's binder, freeing pigment particles that wipe off on a hand or streak down walls onto brick and foundations. A light film after years outdoors is normal aging, and slow-eroding formulas are actually designed into some white sidings; heavy buildup signals a failing finish, cheap paint, or interior paint mistakenly used outside.
What it means
Chalking is the powdery white residue that forms on weathered paint and siding as ultraviolet light breaks down the coating's binder, freeing pigment particles that wipe off on a hand or streak down walls onto brick and foundations. A light film after years outdoors is normal aging, and slow-eroding formulas are actually designed into some white sidings; heavy buildup signals a failing finish, cheap paint, or interior paint mistakenly used outside. It matters before repainting because fresh paint will not bond to powder, so the surface must be washed, scrubbed where heavy, and primed if residue persists after cleaning.
Where it sits in the glossary
Chalking 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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