TL;DR
A casing reveal is the narrow, uniform strip of door or window jamb edge, customarily 3/16 to 1/4 inch, left exposed when trim casing is set back from the jamb's face rather than flush with it. The setback exists for craft reasons: it creates a crisp shadow line, hides small differences between jamb and casing thickness, and leaves wood for the hinge screws and casing nails to grip without splitting the edge.
What it means
A casing reveal is the narrow, uniform strip of door or window jamb edge, customarily 3/16 to 1/4 inch, left exposed when trim casing is set back from the jamb's face rather than flush with it. The setback exists for craft reasons: it creates a crisp shadow line, hides small differences between jamb and casing thickness, and leaves wood for the hinge screws and casing nails to grip without splitting the edge. Finish carpenters mark it with a combination square or a preset reveal gauge and hold it consistent around every opening in the house. Wandering widths around a single door are one of the quickest tells of rushed trim work.
Where it sits in the glossary
Casing reveal 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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