Leaking Valley

mae-ling · 01-07-2012, 09:35 PM

We used 24" inch valley so 12" on each side.

tinner666 · 01-07-2012, 10:11 PM

Yes 24" is good if using the spec of about 6" open at top and 10"+ at the bottom. When using narrower open area, it's too wide and nails end up in the metal. I forget he exact spec'd because 1-1/2" wide at the top and 4" at the bottom on a really long one is the norm here. (From the center)
Weather could have something to do with it too. Here, the worst we get is 110 mph winds with the odd hurricane or tornado, torrential rains up to 2" an hour from tropical storms and the occasional 24" snow.

tinner666 · 01-07-2012, 10:22 PM

Come to think of it, I think that virtually every one I've ever looked at only had 3" to 4" of unexposed metal on the finished valley. Which makes sense when you think of it, because that means that only about 4" of any shingle is unsupported by a nail.
Full weaves are common on the coast where severe weather is the norm.

jeff2201 · 01-07-2012, 11:18 PM

Thanks for all the replies everyone. I've been working and had a roofing company that a friend recommended come out and give me a 8100 quote on a new roof. The reason for trying to get a couple years out of the roof, or a year if I can is that I'm paying down new windows to the entire house and don't want to overextend myself or my HELOC. I like the idea that tinner had, having the extra year could make a huge difference.

jeff2201 · 01-07-2012, 11:22 PM

Quote:

Originally Posted by tinner666

There is one other option that may be easier. Not sure how to explain this, though here's the gist; You could take shingles cut into 12" tabs and starting at the bottom, weave them in, into and under the existing valley shingles, just like the caps are run on the ridge. Less disruptive of the field shingles. By weaving, slide the first one in, then the second goes on top of the back of the first course of field shingles, and under the second row. Weaved, get it? Done correctly, NO lower edges of the weaved valley pieces will buck the water.

I like that idea. alot. Would nailing it to secure it be the best way to go?

tinner666 · 01-07-2012, 11:29 PM

I did neglect to mention that. Yes, nail the outer edges, a bit high. Warm the shingles first! Flexing them while cold and brittle will crack them and they'll split.

They won't lay in perfectly, row for row with the existing. Two might go under, then only 1. Just don't leave any edges bucking water. Slide/weave in 3-4 or more to see how they're going and get a rythym and feel for it. Then, you can start nailing them in place. I wish I could explain it better, but its' going to be some trial and error. Identify and correct the errors before nailing. Pour some water here and there to check water flow and learn from it.

mae-ling · 01-08-2012, 02:01 AM

Thanks Tinner, learnt a new trick.
We usually run one side right through the valley, then cut the other in a line down the valley about 1" off the center.