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Old 12-13-2011, 08:33 PM   #16
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Why Leaking Roof under Dormer / hole in OSB!!!


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Originally Posted by MB1 View Post
???? There is rain in the forecast and I have a hole in my roof....I have to do something to keep the water out....am I missing your humor somewhere?
No humor intended. Has it been leaking for a while? Maybe you can tarp it off for now, securing it with 2x4 nailers.

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Old 12-13-2011, 09:13 PM   #17
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Why Leaking Roof under Dormer / hole in OSB!!!


There hasn't been much rain since I noticed the problem. But now that I've disturbed the area and cleaned out the OSB, it seems fairly exposed. And, I'll be out of town a week over the holiday. Not much comfort with a hole in the roof!
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Old 12-13-2011, 09:19 PM   #18
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Why Leaking Roof under Dormer / hole in OSB!!!


Didn't you say you had a roofer friend? He would know how to lay some plastic, tucking it under shingles where he can, and some stickers where needed (1x or 2x nailers).
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Old 12-13-2011, 09:22 PM   #19
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Why Leaking Roof under Dormer / hole in OSB!!!


http://roofing.owenscorning.com/home...needaroof.aspx
If you know what brand and color of shingles your going to have them install then just buy a bundle and slide a few in under the ones you have now.
DO NOT USE THREE TAB SHINGLES AGAIN>
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Old 12-13-2011, 09:42 PM   #20
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Why Leaking Roof under Dormer / hole in OSB!!!


Looks like a few pieces of step flashing slipped under the edge of the shingles where they meet the fascia and up the fascia board to cover the gap may help some and maybe a roll of flashing tape for any other areas. Still only temporary and may not keep all the water out, but it may help.
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Old 12-13-2011, 09:59 PM   #21
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Why Leaking Roof under Dormer / hole in OSB!!!


Unfortunately, I do not have a roofer friend. Joe, I was going to go with Certainteed's Landmark 30 year product. Is that 3 tab? Ok product? Any reason why you are recommending not going with a 3 tab?

As for sliding shingles under, I think that may work (along with some step flashing with metal shingles along the facia board; however, if water is pooling and getting under the dormer roof, then it will hit the big hole (where the OSB is missing). Even if I shove shingles up there, water will get under them. My thought was to get some metal shingles, caulk the heck out of them on the bottom with Silicone, and shove them up under the dormer where it meets the main roof. Then patch the area with roofing cement and stepping medal shingles down integrated with the stepped metal shingles down below the original (of course as a temporary patch).

My worry is that I will dam the area with the caulk and bring more water in. Which brings me back to applying roof patch to the entire area to keep water from getting in (if that would work), or tarp it
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Old 12-13-2011, 10:07 PM   #22
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Why Leaking Roof under Dormer / hole in OSB!!!


You may cover the big holes with a roll of regular aluminum flashing which you can get up to about 20" wide or so . You can see if that will work but it will have to be lapped correctly and slipped under shingles so water doesn't run under it, of course that is assuming the old osb will hold a roofing nail to put it on with.
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Old 12-13-2011, 10:18 PM   #23
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Why Leaking Roof under Dormer / hole in OSB!!!


Not sure what you'll be using to fix that 'mess', but I'll point out one 'oops' and give you one tip.

The 'oops' is that this is a perfect example of why shingles, or anything else for that matter should extend past the drip-edge. What ever you method you use, metal, SBS, or whatever, be sure and extand past that 'valley outlet' at least 4", and hopefully you will have managed to give that exit a little bit of slope. If it's dead level there, it'll leak anyway without heroic efforts.
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Old 12-13-2011, 10:36 PM   #24
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Why Leaking Roof under Dormer / hole in OSB!!!


The closest similar pic I had was this. This was a roof butted into a wall. The end extends past about 2" from mit's closest contact point in the bottom and the flap of metal is there for the water to follow it and not wick back under the pan.


By heroic efforts, you'd remove enough wood to install a large metal pan under that eave, flashed into the wall of the dormer, and extending well up the roof under the bottom of that 'valley' you have there. Done correctly it would catch any water that wicks back there.

The way it is now, that piece of step flashing under the valley is correct, BUT, the valley by not extending beyond the dripedge is allowing lots of water to run behind it and the fascia. That's why the rotted wood.
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Old 12-13-2011, 10:40 PM   #25
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Why Leaking Roof under Dormer / hole in OSB!!!


Unfortunately, the OSB isn't going to hold a nail in this area around the facia.

Tinner, thanks for the tip although I am not sure I follow it. Are you suggesting that the Dormer Roof get extended out to each side further or narrowed? Also, with regards to your comment on the drip edge, are you saying that the shingles should extend over the drip edge? If so, by how much?

Thank you!
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Old 12-13-2011, 10:48 PM   #26
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Why Leaking Roof under Dormer / hole in OSB!!!


The crickets/saddles (the two, triangular sections of roof, behind the front of the dormer) are not extended far enough out to the sides of the dormer.
That creates an almost, "flat" area of roof at the bottom of the valleys.
Also, the shingles were not "woven" correctly.

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Old 12-13-2011, 10:48 PM   #27
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Why Leaking Roof under Dormer / hole in OSB!!!


Tinner, ok, thank you for your last comment which clarified this for me. The two installers I have talked to just want to install valley flashing (I think a W piece) that dumps the water beyond this corner (at the facia board/drip.) Is that likely going to work in this situation?
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Old 12-13-2011, 10:55 PM   #28
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Why Leaking Roof under Dormer / hole in OSB!!!


No 'W' there. It's not all it's cracked up to be. A large sheet 3'x4' of galvalume with the edges hemmed, and cleated in place, after trimming to fit the structure correctly is what I'd use as Plan A. Start shingle around the edges leaving 80% or more exposed.
Plan B would be 3-4 layers, staggered, of SBS mod-bit.
Plan C would be dimensional shingles but that's another plan all together. I'd probably be starting off on Plan C and be at Plan N by time I got that one finished.
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Old 12-13-2011, 10:56 PM   #29
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Why Leaking Roof under Dormer / hole in OSB!!!


Oh, the Heroic effort with that catch pan underneath would be 'A given' no matter what else I decided to do above it. Plan on doing both sides that way.
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Old 12-13-2011, 10:58 PM   #30
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Why Leaking Roof under Dormer / hole in OSB!!!


PS, roof cement wouldn't be a part in any of my plans. I have to get to sleep now. Hope that helps clear it up.

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