Then install a non corrosive metal valley flashing of 24 minimum width.
How to install flashing on roof valley.
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.
Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing.
Install an underlayment centered in the roof valley.
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.
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.
Remember to caulk the underside of the flashing with a sealant.
Now nail this first flashing at both its far ends.
Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic.
Lap successive sheets of metal flashing a minimum of 12 inches and seal laps.
Roof one side of the valley running the shingles across it.
Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles.
No one of this affirmat.
Architectural shingle installation is especially critical in roof valleys where iko recommends an open valley installation.
Stop nailing 6 inches from the center.
Step 6 install the.
Shingle the other side of the valley the same way.