Dormer Roof Lead Flashing

Proper installation of flashing and counter flashing at the intersection of a vertical wall with a roof surface is required to avoid roof leaks.

Dormer roof lead flashing. 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. Lay a bead of roofing cement along the shingles just below the dormer and bed the metal base flashing into it. 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. According to the federal emergency management agency fema improper roof flashing could lead to wood rot and even deck collapse.

Damaged or improperly installed roof flashing especially around the chimney or dormer is one of the most common causes of roof leaks. A critical juncture that often fails is where these two flashings meet. So chances are if you ve been looking into your roof and its flashing you have questions. 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.

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. The flashing extends at least 4 onto the roof and 8 up the wall. Dormer to roof junction this detail illustrates the first method described above using individual copper flashing squares woven between the shingles tile or slate. Also they require sidewall flashings.