Dormer Roof Lead Flashing

The joint between the copper apron and base flashing is soldered.

Dormer roof lead flashing.

Shed dormers require a continuous strip of flashing along the top of the lower roof plane where it meets the steeper roof plane. So chances are if you ve been looking into your roof and its flashing you have questions. Start with the right flashing. According to the federal emergency management agency fema improper roof flashing could lead to wood rot and even deck collapse.

Dormer to roof junction this detail illustrates the first method described above using individual copper flashing squares woven between the shingles tile or slate. Ideally this custom flashing will have soldered corners but if not carefully notch the metal at the dormer corners and wrap the vertical leg around the corner onto the side wall. 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. The flashing extends at least 4 onto the roof and 8 up the wall.

Because their front and side walls meet the roof in different ways dormers require several techniques to integrate the flashing with the roofing material as well as with the house s water resistive barrier wrb of housewrap or felt paper. Lay a bead of roofing cement along the shingles just below the dormer and bed the metal base flashing into it. Damaged or improperly installed roof flashing especially around the chimney or dormer is one of the most common causes of roof leaks. Our page top photograph illustrates a successful installation of flashing and counter flashing along intersection of a roof surface with the side of a brick constructed dormer.