How To Flash A Metal Roof Dormer

Roof shingle over step flashing.

How to flash a metal roof dormer.

Flashing a dormer in prattville al. 3 install roof shingles to the base of the dormer notching around the corners as needed. Remove the paper from the first piece and press onto cheek membrane piece. Step flashing on roof peak.

If you do not wish to form your own corner flashing you can buy pre bent pieces and cut them to size or use a piece of corrugated aluminum which is easier to bend. One common method is to lay the edge metal under the eaves membrane and over the rake details concrete masonry roofing wrb flashing. Because this type of metal flashing can t be soldered making a leak proof joint where the flashing turns the corner at the bottom of the dormer called for special attention but i have a detail that handled the situation nicely. Reach under the roof overhang and lift up the edge of the first piece of membrane and slide the cheek piece under the first piece of membrane.

Bend the corner flashing tightly around the corner. Slide the membrane up the roof along the wing wall placing it so that the half with the release paper is on the roof. The top joinery of both valleys when they meet on the same plane of roof is shown here. Lay a bead of roofing cement along the shingles just below the dormer and bed the metal base flashing into it.

Since most ordinary homeowners do not have all the necessary know how or significant knowledge of basic roofing principles along with experience of working on an actual roof all day in the sun with the sweat pouring down the face as you work on flashing all the dormers chimneys and roof vents or shingling away for hours on end and doing it right taking on the installation of a metal roof. I have my valley custom made with water trough to help with leaking b. Both the peel and stick membrane and the underlayment should extend up the wall higher than the vertical leg of the step flashing. For photos and the four steps to flash a dormer click the view pdf button below.