Metal Roof Open Valley Flashing Detail

The top joinery of both valleys when they meet on the same plane of roof is shown here.

Metal roof open valley flashing detail.

We ve arranged our superb selection into grp valley troughs for tiled roofs and roof valley solutions for slate roofs. I have my valley custom made with water trough to help with leaking. Roof valleys are like gutters with a steep pitch but the stakes are higher for valleys than they are for gutters in a previous video we covered how to flash roof edges before shingling. Then install a non corrosive metal valley flashing of 24 minimum width lap successive sheets of metal flashing a minimum of 12 inches and seal laps.

Installation instructions often call for avoiding fasteners except clips or through slots but roof penetrations and many flashings like drip gable and end wall flashings are fastened directly and seemingly do just fine. The cant strip can also be constructed as shown in detail 9 5d. In comparison to a closed valley an open valley adds another layer of lining into the valley. The shingles or slate must lap the flashing at least 6.

After the self adhering underlayment is installed across the valley a pre bent metal valley lining is installed. Fold the top over the roof ridge and cut the bottom along the drip edge metal. Details roofing wrb flashing. Grp valley troughs provide you with a durable and cost effective alternative to lead products.

If you can t find it here give our friendly customer services team a call on 01752 692760 and. This valley flashing material can be manufactured from any metal that will resist the effects of weather acid rain and other contaminants. The detail shows a typical open valley flashing for a shingle or slate roof. Two different cants are illustrated.

Lile points out that valleys lined with roll roofing are not as durable. Looking for something specific. Nrca lile recommends that roof valley flashing metal for open roof valleys should be 26 gauge 0 45mm galvanized steel or equivalent noncorrosive nonstaining metal. The sloping roof planes then stop some inches short of this centerline leaving the valley open.

Metal roofing and flashing details are a bit funny that way. Roofs that feature open valleys use v or w shaped metal pieces at the center of the valley. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Recommended procedures of basic valley flashing installation.

With a clean valley you can lay down some peel and stick roofing membrane. The v or w shaped metal pieces used as centerlines could be galvanized copper aluminum zinc alloy or steel coated. Dormer flashing details in 4d.