How To Flash A Roof Valley

Stop nailing 6 inches from the center.

How to flash a roof valley.

Attach the flashing panel in place at the bottom. Fold the top of the flashing over the ridge. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Two ways to flash roof edges.

Use 1 inch galvanized roofing nails. Make sure to cover the gap at the bottom of the raised ridge. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Step 6 install the flashing.

To splice the pieces add roofing cement to the lower piece and install the upper piece with at least a six inch. Install valley battens on both ends of the roof valley then attach first flashing 3 4 inches over the roof flange and another 3 4 inches over the fascia if any is present. Cut the bottom edge and fold it down over the drip edge. Remember to caulk the underside of the flashing with a sealant.

Roof one side of the valley running the shingles across it. Make sure that the end of the flashing panel is perfectly in line with the edge of the roof. Shingle the other side of the valley the same way. Protect the eave from ice dams and sideways rain step one in steep slope roofing is the edge flashing.

One common method is to lay the edge metal under the eaves membrane and over the rake.