How To Install Valley Flashing On A Metal Roof

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.

How to install valley flashing on a metal roof.

Flashing should be installed in all of the valleys. When installing metal valley flashing there are a few things to keep in mind from cutting metal roofing to sealing the flashing. Roof one side of the valley running the shingles across it. Open valley shingle installation.

Lap successive sheets of metal flashing a minimum of 12 inches and seal laps. An open valley relies on metal flashing for protection. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Open valleys have metal flashing to protect this critical area of the roof.

I have my valley custom made with water trough to help with leaking b. The top joinery of both valleys when they meet on the same plane of roof is shown here. Recommended procedures of basic valley flashing installation. Shingle the other side of the valley the same way.

Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. The edge of the roof has thin metal flashing that helps water drip off the roof without damaging the home or causing a leak. Stop nailing 6 inches from the center. That flashing is left exposed so the roof has visible lines of metal running down the valley.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Then install a non corrosive metal valley flashing of 24 minimum width. 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.