This is an example of masonry spalling due to moisture, environmental temperature and hard mortar joints. Moisture migration accompanied with differential movement of the clay brick masonry and “denser” mortar creates an increased brick unit expansion stresses versus the surrounding mortar. The resulting effect debonds the brick exterior face.
Depending on the severity of the masonry spalling and the wall structural state, repairs can range from “maintenance type,” consisting of tuck pointing and coating application (if applicable), to a full masonry wall rebuilding. Repairs are intended to reduce the amount of water absorption from entering the masonry wall and restore the structural integrity of the masonry.