Where should flashing be located to protect masonry from water intrusion around openings and at roof connections?

• A. Behind the masonry at roof-to-wall intersections and above openings; ensure continuous flashing with proper weep holes and terminations.
• B. On the exterior surface only.
• C. Not necessary if joints are sealed.
• D. Only at basement levels.

Answer: (A)

Flashing must be placed where water is likely to penetrate the masonry, and that means behind the masonry at roof-to-wall intersections and above openings. Putting flashing in this position creates a continuous water-shedding barrier that directs any moisture down and out through designed paths, such as weep holes and proper terminations, rather than allowing it to wick into or behind the brick veneer.

At roof connections, flashing stops water from migrating along the joint between the roof and wall, a common intrusion path, while around openings it provides a dedicated drainage route so mortar joints and gaps don’t become bridges for moisture. Continuous flashing around these areas works with step or head flashing details to cover transitions and prevent gaps where water could bypass the barrier.

If you only flashed the exterior surface, water can still get behind the veneer and bypass the barrier. Relying on sealants alone isn’t reliable because joints can crack or move over time. And limiting flashing to basement levels ignores the places where water can enter brickwork at higher elevations and at roof lines.