Depending on how the roofs join you may have to cut a slot to work it in far enough.
Roof gully repair.
This video shows the full repair from removing leaded va.
This video shows the traditional and best way to repair a lead valley on a roof.
Begin by removing the shingles down to the wood sheathing and slip a strip of adhesive ice and water barrier available where roofing repair products are sold under the soffit main roof joint.
This method of lead valley repair is proven to not only be fast and safe wit.
Soup to nuts riley shows the proper way of installing a valley on a roof.
I had roofers in who cleaned repaired and sealed my roof and gave me a guarantee for 10 years but the leak comes back every so often in heavy rain.
Depending on how the roofs join you may have to cut a slot to work it in far enough.
To each other which seems to be lead has a persistent leak.
Begin by removing the shingles down to the wood sheathing and slip a strip of adhesive ice and water barrier available where roofing repair products are sold under the soffit main roof joint.
A gully between two sections of my roof which are at 90 deg.
If you have multiple valleys on your home you may have to consider a complete re roofing job especially if your roof is rather old and will need to be replaced soon.
Soup to nuts riley shows the proper way of installing a valley on a roof.