How To Replace Roof Valley Flashing

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.

How to replace roof valley flashing.

Architectural shingle installation is especially critical in roof valleys where iko recommends an open valley installation. If your roof valley leak is an old repair gone bad consider having a professional repair the leak properly. Stop nailing 6 inches from the center. 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.

Roof mastic applied along sides of valley flashing. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. From drip edge to valley flashing december 25 2018 drip edge metal valley flashing dormer chimney and kick out flashing shed water away from the connections between roofs walls chimneys and other building assemblies.

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. Failure to extend the entire width of the metal valley flashing beyond the eave of the roof. 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. The top joinery of both valleys when they meet on the same plane of roof is shown here.

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. Shingle the other side of the valley the same way. Expert advice on how to repair roof flashing and chimney flashing prevent ice dams and solve other roof flashing problems.

Roof one side of the valley running the shingles across it. While some skylight manufacturers include flashing in their products sometimes roofing professionals have to create it or purchase it separately. Avoid the following common errors. Open valleys have metal flashing to protect this critical area of the roof.

Closed cut valley fully replaced with new metal valley flashing. Fasteners placed in the exposed center area. Pull the nails at that side of the ridge shingles to install.