Leak from Roof From Stove Chimney Flashing

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PK44

Member
Mar 14, 2017
15
New York
Good morning. Long Island got hit with an extraordinary amount of rain which ended up with a leak in my ceiling near the area my wood stove chimney is. Went up on the roof and noticed the following which seems to be the culprit. Looking for some feedback on what I should use to seal these cracked gaps which is where I think the problem originated from.

Thoughts? Any advice on the correct product to reseal this?
Chimney1.pngChimney2.pngChimney3.png
 
If it’s flashed correctly, you should not need any caulking or sealant at all. That honestly looks like a mess. If you can’t afford to have it ripped out and flashed correctly, you could always use roofing tar. Unfortunately, eventually it will crack and deteriorate again. It may last a year, it may last 10 years. No way to tell.
 
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If it’s flashed correctly, you should not need any caulking or sealant at all. That honestly looks like a mess. If you can’t afford to have it ripped out and flashed correctly, you could always use roofing tar. Unfortunately, eventually it will crack and deteriorate again. It may last a year, it may last 10 years. No way to tell.
Welp. Add this to the list of things the previous homeowner installed that were done improperly.

Thanks for the reply.
 
Where is this flashing located in relation to the roof? Is it near the peak? There may be other issues. Can you post a picture of the whole chimney?
 
Roofing tar should not have been used at all. Try to clean the tar off around the top rim of the storm collar as best as possible. That is where the seal is needed. The sealant needs to be flexible to accommodate the heating and cooling of the chimney pipe. There should be a generous bead of good silicone adhesive around the top edge of the cone. I like GE Silicone II for this application.
 
Get a can of good black roof tar And a margin trowel to spread it around. I had a skylight leak too from this wind driven rain blowing the water up under the flashing. This is for the tar that is on the roof shingles covering the flashing.

For the storm collar at the flue pipe, try Begreens suggestion if you can get that tar off. (not easy).

The low pitch on the roof helps the wind drive the heavy rain under the flashing and shingles.

Wear old clothes as is impossible not to get tar on you.
 
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Do you know what brand chimney pipe this is? Does it have a folded or welded seam?
 
Do you know what brand chimney pipe this is? Does it have a folded or welded seam?
Good question.
My roofer friend when trying to find a leak or whenever installing flashing always said "think like water".
And in this case "think like water with a fan blowing hard on it"
 
Older Selkirk pipe had a folded seam. The only way I was able to stop that slow drip when we had that pipe was to run a bead of silicone along the full length of that seam on the first length of pipe coming out of the roof.
 
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FWIW there are two types of silicone, the cheap stuff that uses acetic acid to set the rubber and the expensive stuff which uses alcohol (usually called Silicone 2). In some cases the acetic acid based product can cause corrosion. Clean everything real well and apply a good coat, then repeat every year until you are sick of it and hire someone or DIY the proper fix. I fought a poor flashing job for years on my masonry chimney, I finally had it torn down to below the roof line to fix the flashing and other issues and when the new work was done no leaks and no goop.
 
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It sounds like the roofer messed up and should fix it properly. Slathering goop on a bad issue is not a proper fix.