Abstract
The design and repair of exterior glazed brick walls differ from that of unglazed (normal) brick walls. Water that penetrates a typical brick wall usually enters through mortar joints, through failed sealant joints, and by absorption of the brick and mortar. Much of this water escapes the wall by evaporation from the face of the wall. However, the impervious face of ceramic glazed brick significantly reduces the amount and rate of evaporation of water that enters a wall, thereby exposing the glazed brick cladding to spalling caused by the freezing of moisture trapped in the brick units. In addition, since the glaze will trap efflorescence in the brick, the buildup of this cryptoflorescence behind the glaze can result in spalling of the glazed surface of the brick. Therefore, the prevention of water penetration into the masonry wall and the rapid removal of water that has entered the wall are critical to the successful performance and durability of glazed brick clad walls. This paper discusses the common failure modes of glazed brick walls and the current industry recommendations for the design and detailing of glazed brick walls. A case study of a project that includes the investigation of a wall with spalled glazed brick and the design and installation of new glazed brick on the wall is presented. This paper discusses the specification of glazed brick materials; the difficulties in color matching new glazed brick to existing glazed brick; the design and detailing of a new glazed brick wall; and other repair methods to prevent water infiltration and increase the durability of glazed brick walls.
