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Home Glossary Reveal
Masonry noun

Reveal

/ri-VEEL/

Also known as: window reveal, door reveal, jamb, soffit reveal, splayed reveal

The side face of a wall opening - the internal surface of the masonry between the face of the wall and the window or door frame. The reveal depth equals the wall thickness at the opening and affects how window frames are fixed and window boards are fitted internally.

Reveals must be plumb, square, and of consistent depth for windows and doors to fit correctly. On cavity walls, the reveal is typically closed with a cavity closer to maintain the thermal and weather barrier at the opening edge. Plaster or render is applied to the reveal internally. A splayed reveal is angled outward to improve light entry.

Approved Document L - Conservation of Fuel and Power

Cavity closure at revealRequired - thermal and weather barrier
Thermal bridging riskHigh - requires insulated closer

Window reveals are a significant source of thermal bridging in cavity walls. An insulated cavity closer at the reveal is required to meet Part L thermal performance requirements.