Metal Roof W Valley Installation

Install an underlayment centered in the roof valley.

Metal roof w valley installation.

Roof one side of the valley running the shingles across it. Shingle the other side of the valley the same way. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Best practices for sealing the metal roof valley vary based on the slope of the roof.

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. Allow w valley trim flashing to overhang roof edge so it can be trimmed back flush with roof overhang. Cut the panels from the ground instead of on the roof to avoid damaging the roof with the debris.

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. Lap successive sheets of metal flashing a minimum of 12 inches and seal laps. Stop nailing 6 inches from the center. Recommended procedures of basic valley flashing installation.

How to seal metal roof valley.