Metal Roof W Valley Installation

Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing.

Metal roof w valley installation. Recommended procedures of basic valley flashing installation. 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. How to seal metal roof valley. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles.

Then install a non corrosive metal valley flashing of 24 minimum width. Roof one side of the valley running the shingles across it. Low slope roofs slope less than 3 12 use tape sealant between the valley trim and the panel. Best practices for sealing the metal roof valley vary based on the slope of the roof.

Starting at the bottom fasten w valley trim flashing to purlins or substrate using 1 1 4 roofing nails 1 from trim edge every 24 on center. Stop nailing 6 inches from the center. Shingle the other side of the valley the same way. Allow w valley trim flashing to overhang roof edge so it can be trimmed back flush with roof overhang.

Lap successive sheets of metal flashing a minimum of 12 inches and seal laps.