Water leak..!

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Millertime_9

Member
Feb 3, 2020
49
G72 8ax
Hi all

Had an issue with one of our stoves since we moved in

When it rains, water drips down the outside of the flue pipe and ends up on top of the stove

Its a really old farmhouse, so my worry was an issue with the roof and waters working its way down until it hits the flue pipe then runs down, but I don't think thats it

Ive fired a hose against nothing but the top of the flue pipe outdoors and let the water run down it and sure enough, waters getting in inside
So thats good news I think - least it isnt the roof!

Problem is, ive had someone reseal the cowl and that didnt fix it, so from these pics does anyone recommend where we try next as the culprit?

Thank you
 

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I had a similar issue. I had my local sweep/installer come and take a look. They resealed the flashing and did a water test (essentially what you did, spray the heck out of it) and still leaking. Checked connections, everything seemed OK. Tough part for me was I had to get a roof done anyway so I did that, and the installer also put in a "water diverter" which essentially was bent metal flashing that made a "U" shape around where the stove comes up from the roof making a makeshift gutter that diverted the water to the actual home gutters. After those 2 things, my problem was solved. I also had leaky skylights, so my culprit was most likely the roof. If all connections and sealing looks good, a diverter may not address root cause but may help. It at least did for me.
 
You could try and remove the roofing around that area, and install a new roof flashing. It can be very hard to determine how it's getting in. All you can do is make a major change and hope. I had a leak into my fireplace in BC for months and could not find it. They installed a new top flashing on the chase and I resealed everything. Eventually I determined it was coming from the roof itself. It was a flat roof. Water can start from anywhere, and end up coming through any hole you have. Good luck!
 
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You could try and remove the roofing around that area, and install a new roof flashing. It can be very hard to determine how it's getting in. All you can do is make a major change and hope. I had a leak into my fireplace in BC for months and could not find it. They installed a new top flashing on the chase and I resealed everything. Eventually I determined it was coming from the roof itself. It was a flat roof. Water can start from anywhere, and end up coming through any hole you have. Good luck!
Thank you
Im hoping the fact that I sprayed the hose only on the flue pipe and no other part of the roof and it got in, means theres an issue with the flue pipe, cowl or flashing only?

I didn't wet the roof at all, so if I only soaked the chimney pipe that must narrow down the culprit?

Is there silicone or something where the chimney goes through the lead flashing, or is it normally a "boot style" that goes up?
 
Thank you
Im hoping the fact that I sprayed the hose only on the flue pipe and no other part of the roof and it got in, means theres an issue with the flue pipe, cowl or flashing only?

I didn't wet the roof at all, so if I only soaked the chimney pipe that must narrow down the culprit?

Is there silicone or something where the chimney goes through the lead flashing, or is it normally a "boot style" that goes up?
It's hard to say how yours was done, but you will find out when it comes apart. You are right, the water is getting in right in that spot, it would not matter if water found it way there from elsewhere. I am not a roofer, but it seems to me that lead flashing is very old and the shingles should have overlapped way more. You will probably need to find more of that roofing. Is that slate?
 
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It's hard to say how yours was done, but you will find out when it comes apart. You are right, the water is getting in right in that spot, it would not matter if water found it way there from elsewhere. I am not a roofer, but it seems to me that lead flashing is very old and the shingles should have overlapped way more. You will probably need to find more of that roofing. Is that slate?
Dont worry theres loads of them piled up from falling off, haha its an old roof and does require constant maintenance

Interestingly, I just fired water directly at the flashing only and nothing came in

That further narrows it down then to being a problem with the seal around the cowl OR, if indeed the flue does go into the "boot" bit of the flashing, maybe its not firmly pressed against it or siliconed however it should be?
 
[Hearth.com] Water leak..!


Are those screw-type clamps ? (Like on my liner) I had to cover it tightly with a water proof tape, (basically good electrical tape), and that solved my leak. I refurbish the tape every year when I sweep the chimney.
My system is a SS liner in a masonry chimney, so rain was coming in between the liner and the terra cotta, and soaking the insulation, then dripping into the stove. A VERY disturbing situation. The opening was small, but I knew from prior experience that only a little thumbnail slit in a chimney flash lets in large amounts of water. Just a little roofing cement solved that prior problem at our old house.
I got a drop light down in the chimney and saw light peeking out to identify the hole.
I think you may be right about adding silicone. The secret is to know where to place it.
 
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View attachment 340495

Are those screw-type clamps ? (Like on my liner) I had to cover it tightly with a water proof tape, (basically good electrical tape), and that solved my leak. I refurbish the tape every year when I sweep the chimney.
My system is a SS liner in a masonry chimney, so rain was coming in between the liner and the terra cotta, and soaking the insulation, then dripping into the stove. A VERY disturbing situation. The opening was small, but I knew from prior experience that only a little thumbnail slit in a chimney flash lets in large amounts of water. Just a little roofing cement solved that prior problem at our old house.
I got a drop light down in the chimney and saw light peeking out to identify the hole.
I think you may be right about adding silicone. The secret is to know where to place it.
Hmm thats left field and very interesting as thats the side of the flue the water comes down, shall check that thank you!
 
Go for the easiest solution first. It could be as simple as a failure of the sealant around the storm collar. Clean the old off and replace with a good quality silicone adhesive sealant like GE Silicone II.
 
It is sealed outside, on the top rim, where it contacts the chimney pipe.

[Hearth.com] Water leak..!
 
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It might just be the picture but I see very little or no sealant on the backside of the storm collar.

[Hearth.com] Water leak..!