TL;DR
Oxidation is the chalky, faded surface degradation that develops as sun and weather break down paint binders, vinyl siding resins, and aluminum coatings, leaving a powder that rubs off on a fingertip. The white residue must be washed or treated before repainting, since fresh coatings will not bond to chalk, and pressure washing it off vinyl requires restraint to avoid driving water behind panels.
What it means
Oxidation is the chalky, faded surface degradation that develops as sun and weather break down paint binders, vinyl siding resins, and aluminum coatings, leaving a powder that rubs off on a fingertip. The white residue must be washed or treated before repainting, since fresh coatings will not bond to chalk, and pressure washing it off vinyl requires restraint to avoid driving water behind panels. Its even, dusty appearance distinguishes it from mildew, which darkens and responds to bleach.
Where it sits in the glossary
Oxidation 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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