How To Flash A Roof Valley

To splice the pieces add roofing cement to the lower piece and install the upper piece with at least a six inch.

How to flash a roof valley.

Cut the bottom edge and fold it down over the drip edge. Shingle the other side of the valley the same way. Stop nailing 6 inches from the center. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles.

Attach the flashing panel in place at the bottom. One common method is to lay the edge metal under the eaves membrane and over the rake. Protect the eave from ice dams and sideways rain step one in steep slope roofing is the edge flashing. Make sure that the end of the flashing panel is perfectly in line with the edge of the roof.

Lay the flashing down in the roof valley and start at the lower end of the roof. Remember to caulk the underside of the flashing with a sealant. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Make sure to cover the gap at the bottom of the raised ridge.

Now nail this first flashing at both its far ends. Two ways to flash roof edges. Use 1 inch galvanized roofing nails. 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.

Step 6 install the flashing.