Flashing In A Roof Valley

Shingle the other side of the valley the same way.

Flashing in a roof valley.

From drip edge to valley flashing. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Roof mastic applied along sides of valley flashing. Failure to extend the entire width of the metal valley flashing beyond the eave of the roof.

Stop nailing 6 inches from the center. To understand what makes a valley either closed or open it is important to understand how a valley is constructed. Fasteners placed in the exposed center area. There are two common methods for completing the flashing of a valley in a shingle roof system.

Avoid the following common errors. Valley flashing is metal or sometimes peel and stick material that protects an important area on the roof where two slopes come together to form a valley. This collection of 18 articles animations and videos identifies the critical roof flashing areas. Roof one side of the valley running the shingles across it.

Punctures in the center of the valley. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Some homeowners do not like the look of open valleys while others feel the metal accentuates the roof s shape particularly if copper or painted flashing is used. Closed cut valley fully replaced with new metal valley flashing.

That flashing is left exposed so the roof has visible lines of metal running down the valley. Closed valleys or open valleys.