Metal Roof Valley Flashing Details

Extend flashings 4 6 beyond the building cut along the bend lines ap ply sealant and fold the side flaps in and the top flaps down to cap off the ends.

Metal roof valley flashing details.

Lap successive sheets of metal flashing a minimum of 12 inches and seal laps. Mc11 head wall metal flashing. Factors that influence flashing size shape and endlap requirements include roof pitch roof geometry slope length and climatic factors such as heavy snowfall or rainfall. Mc14a chimney flashing step type.

Some roof conditions such as valleys may require a longer endlap and or a larger flashing to properly drain moisture from the roof. Mc12 pan flashing roof to sidewall. Fold the top over the roof ridge and cut the bottom along the drip edge metal. Lile points out that valleys lined with roll roofing are not as durable.

Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Mc12a pan flashing roof to sidewall 2. Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic. Product overview w valley flashing protects the critical area of your roof where two slopes come together to form a valley.

First clean the debris out of the valley including sawdust nails and whatever else is in there. For example in metal roofing systems valleys are commonly fabricated with hems but can also be fabricated without them in which case they could still be used for metal roofing or any other type of roofing. Secure with pop rivets or stitch screws. 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.

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. With a clean valley you can lay down some peel and stick roofing membrane. When properly installed w valley flashing will reliably channel run off water down the roof and into the gutter. Mc11a head wall metal flashing 2.

Mc12b metal flashing options. Installation of sheet metal roofing panel over the gable flashing after our first metal panel is installed we use a system specific metal cap that goes around and enwraps the gable trim and the outer edge of the first metal panel which is what secures holds them together on the outer edge of the system as seen in the picture above. Clip the top corner of shingles along valleys to keep water flow toward center of valley. Endlap flashings a minimum of 6 and seal the lap joints with sealant.

Valley flashings are custom fabricated to any measurements and angles and usually measure 10 in length but can also be bent in 12 lengths.