TL;DR
Mil thickness is the measurement of a coating's depth in thousandths of an inch, the unit by which paint and roof coating specifications are written and verified. Manufacturers state a wet film thickness to apply and the dry film that must remain — an elastomeric roof coating may call for 20 wet mils per coat, while wall paint dries near 1.5 per coat.
What it means
Mil thickness is the measurement of a coating's depth in thousandths of an inch, the unit by which paint and roof coating specifications are written and verified. Manufacturers state a wet film thickness to apply and the dry film that must remain — an elastomeric roof coating may call for 20 wet mils per coat, while wall paint dries near 1.5 per coat. Crews check it with wet film combs during application, since thin spots are where coatings fail first.
Where it sits in the glossary
Mil thickness 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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