Tempo:
Through-Wall Flashing
Cap Flashing
A through-wall flashing intercepts and directs any water flowing down the cavity to the exterior (see Figures 120 and 121).
Parapet walls require a metal cap flashing to prevent water from penetrating from the top of the wall. Since a cap flashing sheds water, it must be sloped toward the roof to prevent staining of the exterior cladding. In addition, it cannot be made waterproof at the joints, and requires a secondary, continuous and waterproof flashing below it.
120 Through-wall flashing
cavity
Dampproof Flashing
flashing
121 Through-wall flashing at foundation
Precast concrete, stone masonry or brick units known as “copings” close the tops of masonry walls or act as window and door sills. These units also serve to prevent water from entering the top of the wall. If the copings are installed in sections, water may leak through the joints. A dampproof flashing should be placed between the coping and the top of the masonry wall to prevent water from penetrating into the wall below (see Figure 122). Using a dampproof flashing is also good building practice if copings or sills without joints are used. 122 Dampproof flashing
cavity dampproofing flashing (flexible, self-adhering rubberized asphalt membrane)
weep holes through wall flashing
exterior finish
sheathing
Cap Flashing
A through-wall flashing intercepts and directs any water flowing down the cavity to the exterior (see Figures 120 and 121).
Parapet walls require a metal cap flashing to prevent water from penetrating from the top of the wall. Since a cap flashing sheds water, it must be sloped toward the roof to prevent staining of the exterior cladding. In addition, it cannot be made waterproof at the joints, and requires a secondary, continuous and waterproof flashing below it.
120 Through-wall flashing
cavity
Dampproof Flashing
flashing
121 Through-wall flashing at foundation
Precast concrete, stone masonry or brick units known as “copings” close the tops of masonry walls or act as window and door sills. These units also serve to prevent water from entering the top of the wall. If the copings are installed in sections, water may leak through the joints. A dampproof flashing should be placed between the coping and the top of the masonry wall to prevent water from penetrating into the wall below (see Figure 122). Using a dampproof flashing is also good building practice if copings or sills without joints are used. 122 Dampproof flashing
cavity dampproofing flashing (flexible, self-adhering rubberized asphalt membrane)
weep holes through wall flashing
exterior finish
sheathing
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