Flashing Shed Dormers

Shed dormers require a continuous strip of flashing along the top of the lower roof plane where it meets the steeper roof plane. Also, they require sidewall flashings. A critical juncture that often fails is where these two flashings meet. Use taller pieces of step flashing towards the top, so the pieces can be bent over the dormer roof to help keep out snow and wind-blown rain (Shed Dormer Flashing, below).

Figure: Shed Dormer Flashing
The top corners of a shed dormer are particularly susceptible to leaks. Use tall pieces of sidewall flashing, combined with a lead flashing patch.
The top corners of a shed dormer are particularly susceptible to leaks. Use tall pieces of sidewall flashing, combined with a lead flashing patch.


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