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What’s the best way to apply three tab roofing in a valley? I have only woven them but I hear that open valley’s and closed cut valley’s have their advantages. Are climates and weather conditions a factor????
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I'll leave the answer to the roofing experts. I'm still a novice.
But I will tell you that we have all three in this part of the country (Michigan) with good results from each.
blue
*Stu, the key to your question depends on the material that is used to form the valley. An open valley can be created with 90# roll roofing or a metal valley material. A closed valley is made with the shingle being installed as a roof. For the open valley made of 90# you must realize that the material does not carry much of a warranty compared to your shingles.Most manufacturers mandate that the material be cut to lengths of 10 feet (this is to reduce shrinkage, a common problem with 90#)and the 90# does not carry much more than a 5 year warranty. An open valley made of metal is great in areas that tend to have lots of snow and or ice. In west michigan most homes near lake michigan have metal valleys. A closed valley made with the shingles is a great way to get your warranty in the area that carries the most water.One thing to consider also is the pitch of the roof and any debries that may be on the roof--leaves,twigs and ice/snow--especially with 3in1 shingles.On a low pitch the cut outs tend to trap all kinds of stuff in the valley.This would be a good place to use metal in an open valley especially if the house is in the woods. Most roofers have their favorite type of valley construction due to familiarity of materials, speed of application or the old "we've allways done them that way". Hope this info helps.
*I was going to suggest you do a search, cause I know that this has been discussed before, but I couldn't find the discussion.What does the shingle wrapper tell you to do?Rich Beckman
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Thanks Thom, that was helpful.
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IMHO, open valley with metal is the only way to go, unless you really want to repair the woven or cut valley about 5 years before the rest of the roof goes (or won't be there anymore and are willing to let the next guy worry about it.) The biggest (one of the) cause of wear on a roof is water, and the valley's carry the most water.
In my neck of the woods (NW Ohio) the woven and cut valleys on three tab start to look pretty bad at about 15 years.
Bob
*Stu, Some sage advice from my favorite resident roofer can be found in these two threads. Sierra Hotel These two should resolve most of your valley questions. There may be a few other pertinent threads buried in the archives. Bring a flashlight and shovel before you go looking, though.FAQ it.
*Archives, archives and archives. This question has been discussed to death. Do a search on "Valley", and there were discussions in 1998 and 1999 with lotsa responses.I like cut valleys. Nice clean look. I hate open valleys, with the sheet metal exposed. It just looks terrible.I also hate woven valleys, because one can see the bulge, which gets worse if you re-roof over the whole mess.
*Scooter,When this thread started, I tried searching for "valley" and, although I got a lot of returns (four pages worth) the two good discussions that Mongo links to above were not represented. I don't know how Mongo found them.Rich Beckman
*Closed cut valleys with ice and water shield under all looks great, is easy to produce, easy to go over, gives you shingle warranty, lasts as long as the rest of the roof if not longer, and is less expensive than a double valley bent copper flashing job which I also think is worthy and very indestructable...near the leaky roof(no ice and water), near the stream,aj
*Isn't that such a pain, Rich?I initially did the same thing Scooter did, ran a search using various words "valley, open, closed, weave". I laughed (disparagingly) at the search results. Discussions on "Napa Valley", etc, came up. The thing is that I even knew the two threads I wanted to find, but it took several tries to find them. I eventually came up with the right combo of words to find the threads.Makes me want to push even harder for this revamping of the SEARCH/FAQ we've been writing about.
*Here in California, My roofing supplier says metal open valley with a ridge in the center of the valley with 3 tab or anything else.
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Once Again ....Thank you Gentlemen. Having some outside opinions really helps.
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What's the best way to apply three tab roofing in a valley? I have only woven them but I hear that open valley's and closed cut valley's have their advantages. Are climates and weather conditions a factor????
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In my opinion it does not matter what style of
valley is formed. The key is putting the good
ice and water sheild under it. It does not work with open valley because the sun eats this material quickly.
John Keller