How To Replace Roof Valley Flashing

Closed cut valley fully replaced with new metal valley flashing.

How to replace roof valley flashing.

While some skylight manufacturers include flashing in their products sometimes roofing professionals have to create it or purchase it separately. Shingle the other side of the valley the same way. W type valley flashing is more rigid for handling so it stays straight and it stops waler rushing down one side of a roof from rushing back up the other side. Where valleys run from the edge of the roof to a ridge trim the flashing to fit under the corresponding side of the ridge shingles.

Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. The top joinery of both valleys when they meet on the same plane of roof is shown here. When a roof leaks the problem is often due to leaks in and around the metal roof flashing that protects roof edges valleys and the junctions between roofing and obstructions such as chimneys dormers and vent pipes. Open valleys have metal flashing to protect this critical area of the roof.

Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Punctures in the center of the valley. The edge of the roof has thin metal flashing that helps water drip off the roof without damaging the home or causing a leak. Architectural shingle installation is especially critical in roof valleys where iko recommends an open valley installation.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Some shingles and flashing may need to be removed and replaced but the roof can usually be saved with a good quality repair. Stop nailing 6 inches from the center. I have my valley custom made with water trough to help with leaking b.

Roof mastic applied along sides of valley flashing. Pull the nails at that side of the ridge shingles to install. Avoid the following common errors. If your roof valley leak is an old repair gone bad consider having a professional repair the leak properly.

Fasteners placed in the exposed center area. Learn the three methods of shingling a roof valley the advantages and disadvantages of each how to choose valley flashing and how to shingle an open valley. Roof one side of the valley running the shingles across it.