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with sheet metal (Figure 126). The saddle should be suitably flashed at the roof and at the chimney. A saddle is not required if the metal flashing is carried up both the roof and the chimney to a height at least equal to one-sixth the chimney width. On roof slopes behind a chimney, the flashing should extend up the roof and up the chimney to a point equal in height to the chimney counter flashing, but not less than 150 mm (6 in.) or 11⁄2 times the shingle exposure. Open joints or laps should be soldered or sealed, or a locked joint used.
Drip Flashing Drip flashings intercept moisture that has entered behind the cladding and direct it to the outside, as well as redirect water flowing down the face of the wall to prevent it from dripping down on the materials below. A drip flashing should be inserted between two different siding materials (for example, siding above stucco) or between different materials and components. To prevent water from entering the joint, a preformed drip should extend from behind the siding out over the stucco to a drip at the outside edge (Figure 9).
126 Chimney flashing
saddle required by code where width of upper side of chimney exceeds 750 mm (30 in.)
one-piece saddle rubberized asphalt sheet installed on sheathing before installation of metal flashings