Installing Valley Flashing On Existing Roof

Then install a non corrosive metal valley flashing of 24 minimum width lap successive sheets of metal flashing a minimum of 12 inches and seal laps.

Installing valley flashing on existing roof. Roof one side of the valley running the shingles across it. Lay the flashing in a way that an inch of the flashing protrudes over the edge of the upper flange of the batten. Install an underlayment centered in the roof valley. Remember to caulk the underside of the flashing with a sealant.

Use roofing nails to install the l shaped flashing flush with the roof and wall then cover it with roofing cement and reattach the roofer s felt. No one of this affirmat. Finally reattach all shingles removed in the process. Stop nailing 6 inches from the center.

Step 3 install the flashing. Many roofers cut the shingles across because they say it s safer. Now nail this first flashing at both its far ends. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles.

In this video i show you how i do the valleys on a shingle roof. 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. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Place the flashing on the upper portion or the upper flange of the batten.

Install the valley battens on the sides of the roof that you want to place the valley flashing. Shingle the other side of the valley the same way. Recommended procedures of basic valley flashing installation.