Roof Valley Flashing Installation

Before you apply the flashing you ll need to lay down a waterproof membrane.

Roof valley flashing installation.

Many roofers cut the shingles across because they say it s safer. Install an underlayment centered in the roof valley. Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic. The edge of the roof has thin metal flashing that helps water drip off the roof without damaging the home or causing a leak.

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. Drip edge metal valley flashing dormer chimney and kickout flashing are types of roof flashing that shed water away from the connections between roofs walls chimneys and other building assemblies. 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 5 begin installation. 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. Install the underlayment as directed by the manufacturer then set the valley flashing on top of it.

No one of this affirmat. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Architectural shingle installation is especially critical in roof valleys where iko recommends an open valley installation. There are two common methods for completing the flashing of a valley in a shingle roof system.

Lap successive sheets of metal flashing a minimum of 12 inches and seal laps. Now nail this first flashing at both its far ends. Stop nailing 6 inches from the center. Especially if you live in an area that gets a lot of snow and ice.

Remember to caulk the underside of the flashing with a sealant. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Then install a non corrosive metal valley flashing of 24 minimum width. For the valley areas of the roof you will be using valley flashing.

In this video i show you how i do the valleys on a shingle roof. Closed valleys or open valleys. 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. 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.