A.Corresponding Editor Henri de Marne responds: There is a product called the Flash Filter Vent that is designed for the application you face. This shed roof vent has a low profile and comes in dark brown, black, white and mill finish. It is available from AVI, a division of CertainTeed (800/247-8368).
The vent replaces the apron flashing normally installed at the joint between a wall and a shed roof. It requires removing the bottom course of the siding and lifting the housewrap or felt paper to insert its 4 1/2-inch leg against the wall sheathing.
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