The copings on the top of many masonry walls are made flush with the exterior face, rather than projecting and providing drips. Are there any potential problems with this design?

It is best to project the copings beyond the face of the wall and provide a drip. Brick Industry Association (BIA) Technical Note 36A states that the interior face of the drip slot cut in the bottom of the stone should be 1-inch from the face of the wall. This design provides good protection for the masonry beneath the wall.

When the coping is flush at the face of the wall, rainwater or melting snow and ice on top of the coping can flow down the face to penetrate the top of the masonry wall. Providing a drip prevents this problem from happening.

If copings are provided flush at the base of the wall, a metal flashing should be used beneath the coping that extends out beyond the face and is bent down at a 30 to 45 degree angle to form a drip. The flashing edge should be hemmed in areas where copings are accessible to people because the sharp edges of sheet metal easily cut skin.