Metal valley flashing is installed over the underlayment but under the edges of the shingles.
No flashing in valley of roof.
Where siding is installed on a wall abutting a lower roof we can run the lower roof head flashing or if along a roof side its step flashing up under the siding provided the upper bend of the flashing is tall enough to extend an inch or more up under the siding and still leave a couple of inches or more of clearance between the siding bottom edge and the roof surface.
While some skylight manufacturers include flashing in their products sometimes roofing professionals have to create it or purchase it separately.
Roof mastic applied along sides of valley flashing.
Extra nails may increase the risk of leaks.
The edge of the roof has thin metal flashing that helps water drip off the roof without damaging the home or causing a leak.
Moving up the valley install any additional roof flashing as required to cover the entire length.
Avoid the following common errors.
Fasteners placed in the exposed center area.
To secure the roof valley flashing nail it down carefully.
In this open valley style the shingles over each section of roof do not touch.
Roof flashing is a thin sheet of galvanized steel installed to channel rainwater away from important areas of the roof.
Open valleys have metal flashing to protect this critical area of the roof.
Drip edge metal valley flashing dormer chimney and kickout flashing are types of roof flashing that shed water away from the connections between roofs walls chimneys and other building assemblies.
To replace a roof valley on most roofs the ridge capping at the top will need to be removed and later reinstated after the valley has been changed.
Punctures in the center of the valley.
Only nail at the edges with only enough nails to hold it in place.