Bad weave in shingles?

How poor of an installation is this valley weave? Could this be a future cause of trouble where water could seep under the weave? The yellow arrow shows the direction of the slope of the roof where the water has the potential of having a stronger flow/runoff. The red line identifies the actual valley of the roof and you can see where the cut ends. The shingles at the bottom are staying with the roof plane that is a slightly lesser pitch.


Open weave or closed cut…makes no difference as long as its done properly and in accordance to manufacture specs…however without breaking the seal of the shingles there is no way for you to tell on a dry day…if there are no water stains then move on.


Looks good from here.

The cut of shingles (or lack of cut) is not consistent. Looks like water would run under at the blue line, possibly other places. To me, doesn’t look like roofer understood what he was doing.


Shingles on the right side of the blue line (lower velocity runoff) should have been run through onto the adjacent roof. Shingles from the steeper roof should have been cut parallel to the valley. I can’t tell from the photo if that’s how it’s done.

That’s how I believe it should have been done, also. It wasn’t. There was a myriad of other issues with the roof, so a licensed & qualified roofer was highly suggested. This was a 55+ community and house was built in 2005. Some siding issues too.

Linda is thinking along the same lines as I was.

Thanks for the remarks gals and guys.


I do not see a cross weave here I see a bad job.I hold a roofing license but have not upheld it for over 20 years I bet.It should have been valley-ed with tin of galvanize metal opened or closed.Even a closed woven shingle would not have shingles that are cut.NONE.The sewing is perfect.What I see here is an inexperienced roofer that did not know how to finish of the valley.
If you run into this and when ever you look at shingles.Lift the first course and you should see everything -drip ,anti icing,felt starter and first shingle.look in valley for how high it goes up each side 9 12 14 inches.Valley Open (cut at top to widening when it comes to the bottom)or (closed) all you see is shingle.