Then install a non corrosive metal valley flashing of 24 minimum width.
Valley flashings for metal roof.
Use 1 inch galvanized roofing nails.
The valley flashing shall extend not less than 8 inches 203 mm from the centerline each way and shall have a splash diverter rib not less than 3 4 inch 19 mm in height at the flow.
Lay the flashing down in the roof valley and start at the lower end of the roof.
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.
Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic.
Description documents preformed valley flashing is used to channel water down the roof into the gutters in the roof valley area.
Gibraltar drip edge flashing can be used with asphalt shingles or metal roofing panels.
Drip edge metal valley flashing dormer chimney and kick out flashing shed water away from the connections between roofs walls chimneys and other building assemblies this collection of 18 articles animations and videos identifies the critical roof flashing areas illustrates durable roof flashing details and shows how to flash roofs right in the real world.
Lap successive sheets of metal flashing a minimum of 12 inches and seal laps.
Roof valley flashing shall be of corrosion resistant metal of the same material as the roof covering or shall comply with the standards in table r905 10 3 1.
Make sure that the end of the flashing panel is perfectly in line with the edge of the roof.
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.
When properly installed w valley flashing will reliably channel run off water down the roof and into the gutter.
Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing.
First clean the debris out of the valley including sawdust nails and whatever else is in there.
Install an underlayment centered in the roof valley.
Step 6 install the flashing.
Lile points out that valleys lined with roll roofing are not as durable.
Overview w valley flashing protects the critical area of your roof where two slopes come together to form a valley.
It s bendable for various pitches.
Be sure to check local building codes to ensure you have the proper width for your application.
The extra kick at the bottom of the face directs run off away from the structure.
Attach the flashing panel in place at the bottom.
Remember to caulk the underside of the flashing with a sealant.
Fold the top over the roof ridge and cut the bottom along the drip edge metal.
