Valley flashing with architectural shingles

EdfromMaryland · Jul 29, 2014

I apologize if this has been covered already but I could not find the information I need. I am reroofing my house - I am not a roofer- but have done it before and it did not leak. I am using architectural shingles and need to cover a 10-12 foot valley. I have been told that because the architectural shingles are thicker I should not attempt to weave them;instead I should do an open valley with exposed metal flashing or closed valley which has been cut so both sides which will sit in the valley better/flatter. I have ice shield and will put this down on the valley first. I was then planning on putting a metal piece of flashing and putting roofing nails along the side of it to hold it in place- avoiding nailing through the flashing. I purchaed a piece of valley flashing from Home Depot it seems to be about five to six inches wide on both sides. However the flashing that was on the roof before is about 18 inches wide on both sides. Is this small piece of flashing sufficient? Is it better to lay one side, cut them at the center of the valley then lay the other side and cut them also at the center so they might lay flatter? Maybe put some roofing cement under each of them?. Or is it better to expose the metal flashing 3 inches on each side from the bottom as I read on another site?

I really appreciate your help

Ed

joecaption · Jul 29, 2014

Why not go on the web site of the company that made the shingles and print out there install direction?
All three types of valleys will work.
Valley flashing needs to be 24" wide.
Any flashing I've seen at the box stores is to thin.
The stuff I use has to be bent on a break.
Valleys need to be wider at the bottom then the top.

jagans · Jul 29, 2014

Hi Ed,

Google/Images/ Closed Cut Valley. If your sheathing runs into the valley and you have no gap to speak of, no metal is needed. Run a full sheet of ice dams centered on valley, then run your lapped felt into the valley to about 6 inches from the center-line then install shingles as shown in illustration. If needed you can install the metal under all so there is support through the angle change. Very minimal nailing is necessary to hold metal, like 32 inches apart along the edge. Do not nail through metal laps for any reason. Good luck to you.

EdfromMaryland · Aug 1, 2014

thanks

Thank you both very much. I went to the Tamko website and they have anice short vidoe that helped a lot. I am not going to use metal as it looks like the sheathing is pretty solid and I am using ice dam

I really appreciate the help
Ed

Valley flashing with architectural shingles

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