Install an underlayment centered in the roof valley.
How to replace roof valley flashing.
Cut each side of the flashing at the lower end to conform with the corresponding edges of the roof using sheet metal.
Cut the bottom edge and fold it down over the drip edge.
Now ask a family member to stand inside the house under the roof valley and then standing on the roof pour a bucket of water onto your handiwork.
Recommended procedures of basic valley flashing installation.
A properly flashed roof valley should have an ice and water shield installed with roofing felt being properly secured over the ice and water.
Apply an approximately 3 inch.
Pry and lift off the flashing.
Make sure to cover the gap at the bottom of the raised ridge.
Do not drive nails into the flashing.
Then install a non corrosive metal valley flashing of 24 minimum width.
With underlayment and flashing installed apply shingles up to one side of the flashing.
To replace flashing around the vent pipe first remove the shingles covering the flange at the back and sides.
Start at the lower end of the valley.
Fold the top of the flashing over the ridge.
To splice the pieces add roofing cement to the lower piece and install the upper piece with at least a six inch.
How to do it.
Position a new vent pipe flashing over the vent push it down into place and nail where shingles will cover it.
Place the new piece of sheet metal valley flashing in the valley with the raised center aligned with the center of.
Caulk any openings left and made by the flashing process with a suitable sealant then dust the flashing once it is dry and paint over with granule paint available at hardware stores of your desire.