Excess mortar squeezed out of joints falls behind the veneer and builds into dams on the through-wall flashing and plugs in the weeps. Water then backs up and leaks inward or saturates the brick. Masons use mesh mortar nets at the base, bevel their beds and clean the cavity. Leak investigators cut a few brick out to check.
Pulled two bricks at the shelf angle and the cavity is packed solid with mortar droppings.
Also heard as
- droppings
- cavity debris
Related terms
Weep
An opening at the base of a wall or window system that lets collected water drain out.
Through-wall flashing
Flashing that runs from the back of a masonry cavity out through the wall face to drain water outside.
Flashing
Thin sheet metal or membrane installed at joints and interruptions in a wall or roof to direct water back outside.
Efflorescence
White crystalline salt deposits left on masonry or concrete as water moving through it evaporates.