you are not really supposed to install dimensional shingles like that, are you?
I did my woven valley 7 years ago and it doesn't really build up with Debris.
It is North East Facing.
When I did it there was an article in Fine Home Building stating that it was the strongest valley.
My home is under construction and we went with my roofers suggestion of the Metal w valley. They look so much better.
My roofer said, and I love this "Who did you hire to roof the garage?" I replied "I did it myself." He replied "I'll do this roof for you on one condition - you never roof another job"
Love it.
On my defence it was my first roof.
I have never done a woven or cut valley for two reasons. The first being I think it looks less finished than then a W metal valley. The second is that roofs who seem to have those types of valleys around here fail faster than those without. Maybe it is because of the huge differences in temperature, the snow just sitting on it for months or improperly installed. I really don't know.
Slyfox, I just did an inspection on a 7 year old roof a few weeks back with an open metal valley. The install was so poorly done that there were actually nails in the exposed part of the valley. I mean, not two or three nails but around 8 and the dang thing never leaked I was told.
How some leaks don't show up inside the home still amazes me sometimes.
The re-roof we did the week before last had a little over 80' of walls,
the last roofers "22 years ago" installed a starter shingle than placed their first 5x7 step flashing on top of it and than placed all the rest of the 5x7 steps one after another with roughly a 1" over lap on each and nailed them down, the ran their shingles simply laid over them instead of laced into them.
All 5 walls leaked, but, the leak built up at the bottom "eave' end and all tho it destroyed the overhangs it never leaked inside the home.
We even cored the walls under the leaks, exterior and interior, and found no rot on the wall studs/structure.