Mil thickness

Definition

The coating depth a commercial specification calls for, measured wet or dry with a gauge.

Why It Matters

Commercial and industrial paint work is bought by film thickness, not by number of coats, and an inspector with a gauge decides whether the job passes. A crew that sprays thin makes its production rate look excellent and then fails the reading, and repaints at its own cost. Ask whether any job has been rejected on thickness in the past two years and what the rework cost. Repainting a finished building is a margin event large enough to explain a bad year by itself.