A roof valley is very prone to leaks especially if you have an older roof.
Roof valley tar.
Move to the highest end of the valley and work your way down cleaning shingles from both sides of the valley whether they re damaged or not.
Woven closed cut and open.
Clear any debris in the roof valley and surrounding area.
Built up roofs or burs also called a tar and gravel roof is a well established and popular style of flat roof that is made up of alternating layers of roofing felt or fiberglass and asphalt that is applied with heat which combine to make a long lasting sturdy roofing system.
Stop nailing 6 inches from the center.
Lay shingles and mark center roof one side of the valley running the shingles across it.
Lay one and two tab shingles as you near the valley so full size shingles will run across the valley.
Roof valleys are troughs that discard runoff water where two sections of sloped roof meet.
I swear it is the fastest way out there.
A roof valley is formed where two roof slopes meet.
Take a close look at how i paper the 30 in the center of the valley.
This is how i paper my vallies.
The valleys on many older houses comprise layers of roofing paper which can deteriorate over time.
Take measurements of your roof flashing most flashing is 14 inches wide but yours may vary.
Essentially there are three main ways to shingle a roof valley.
Water collects in a valley to flow off the roof.