Fold the top over the roof ridge and cut the bottom along the drip edge metal.
Valley dies into roof.
With a clean valley you can lay down some peel and stick roofing membrane.
Asphalt shingles roofing how to install valley by roofrepair101 more about roof installation at.
All of the shingle rows will need to be lined up correctly.
Essentially there are three main ways to shingle a roof valley.
This type of roof is also called broken back hip and valley roof because the main hips are intconeected by the rafter of gables on one side and the rafter of the valley on the other.
The following photos illustrate removal and replacement of a closed cut valley with new open metal valley shingles being removed in closed cut valley.
Such buildings may have more than four hips in the roofs and they form valleys at the inside corners.
Then rather than cutting the shingles on the high volume roof plane a row of shingles is installed with the exposure edge facing the valley center.
It installs and looks almost the same as a regular cut valley where the shingles on the low volume roof plane are installed first and pass through the center of the valley by at least 12 in.
A roof valley is formed where two roof slopes meet.
Draw a 2 inch self stick flashing down the center.
Then lay the shingles on the other side of the roof and again stretch them across the valley a little.
Water collects in a valley to flow off the roof.
Entire width of new metal flashing properly extends over fascia at bottom of roof.
All shingles removed from closed cut valley.
You may notice although it can sometimes be hard to see some areas where the roof drains onto lower pitched or reverse pitched areas that don t naturally drain.
First clean the debris out of the valley including sawdust nails and whatever else is in there.
Ice barrier underlayment installed in roof valley.
Woven closed cut and open.
No need for precise measurement.
Pros of woven valley shingle installations.
You have to cut the shingles back to 1 inch from the centerline.
Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks.
A woven valley shingle installation is one where the shingles from both sides of the roof valley extend over the valley and weave together overlapping courses alternately.
This layering will help direct the water into the valley and down the roof preventing leaks.
Dead valleys occur when two slopes come together in a way that does not allow proper natural drainage or very slow drainage.
This is known as a dead valley.