Condensation Dripping

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Trojan99

New Member
Jan 23, 2021
10
Iron River, MI
I do not know anything about wood stoves. I bought a cabin in the UP of Michigan. I was assured stove was just cleaned and serviced. There were a few drip marks down the pipe, but previous owner had a roofer out and everything looked fine. The previous owner never spent winters in cabin and did not heat cabin.

Since buying cabin, we keep heat on and visit cabin in the winter. During the summer there were no drips, even in downpours. However, during really cold winter days such as today (1 degree), there is condensation on the outside pipe and inside the house there is dripping down the stove pipe and also from the rectangular corner of the pipe plate on the ceiling. The dripping is constant. I don’t think there is an issue when we leave cabin and temperature is belo 50 degrees. I can’t be sure though.

The stove is a Pacific Energy. There is no attic. I have no idea what type of pipe. I have never even used the stove. Water is clear. I will add photos. Any suggestions on chimney guys in UP? I had someone out in the summer and the quote was $2000 for new different type of pipe. I was wondering if there is a sleeve that could go around outside pipe to stop condensation?

Thanks in advance for your help!
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Looks like it might be Selkirk chimney. If it is condensation, that is a hard problem to solve. There is a very cold pipe poking into a warmer, more humid room. Starting a fire and getting the pipe hot should help.

FYI, the stovepipe should have been done in double-wall instead of single-wall. Too much heat is lost out of the stovepipe in long runs. This can lead to excessive creosote accumulation when the flue gases are cooled to below 250º.
 
Great write up with all the pictures and video.
Wow interesting. Especially the fact that you get condensation even though it hasn't been used. Correct? If thats the case, it seems more like a building question rather than the woodstove- even though it is a woodstove but even when it is cool it has condensation.
Any other fixtures or areas that get both extremes and you see moisture there too?
 
Great write up with all the pictures and video.
Wow interesting. Especially the fact that you get condensation even though it hasn't been used. Correct? If thats the case, it seems more like a building question rather than the woodstove- even though it is a woodstove but even when it is cool it has condensation.
Any other fixtures or areas that get both extremes and you see moisture there too?

Thanks for reply. Nothing else leaks. Just the the stove pipe. And in response to using stove, we haven’t used it for the year and a half we have had the cabin.
 
Looks like it might be Selkirk chimney. If it is condensation, that is a hard problem to solve. There is a very cold pipe poking into a warmer, more humid room. Starting a fire and getting the pipe hot should help.

FYI, the stovepipe should have been done in double-wall instead of single-wall. Too much heat is lost out of the stovepipe in long runs. This can lead to excessive creosote accumulation when the flue gases are cooled to below 250º.

Thanks for your response! I heard the guy down the road has the same issue. Same builder. We are all seasonal, and he doesn’t come up too often. If I had his contact info... My worry is the damage to the ceiling.
 
This seems like an issue with lack of insulation and/or lack of vapor barrier. Also, single wall pipe should have been double wall but this shouldn't be the cause of the moisture problem.

Eric
 
Not a scientific approach here, but I would change the single wall pipe to double wall, my rational here is that the single wall pipe is conducting to much heat and radiating it off at the connection to the outside metal on the black class a pipe which then is hitting the support box and causing the focused condensation, if you change to the double wall pipe the outside skin of the dvl will be much cooler and won't conduct heat into the class a skin. This may not be the fix all, but its fairly cheap alternative to try and like what others say, if it fails to stop the condensation, you'll have warmer flue gases anyway fixing a possible performance issue down the road.
 
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I'm thinking with the deep snow on the roof, and the chimney heat, you created a ice dam. It then gets around the flashing. Anyway to clear the snow from that area?
 
Just a thought...if it has set for awhile. Assuming that you had it all checked and its good to go. I'd fire it up and run it for a few days.
 
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I'm thinking with the deep snow on the roof, and the chimney heat, you created a ice dam. It then gets around the flashing. Anyway to clear the snow from that area?
I’m willing to try anything. Last winter, before I I realized it could be condensation on outside pipe, I did shovel. It almost seemed like condensation got worse. Could be my imagination.
 
Not a scientific approach here, but I would change the single wall pipe to double wall, my rational here is that the single wall pipe is conducting to much heat and radiating it off at the connection to the outside metal on the black class a pipe which then is hitting the support box and causing the focused condensation, if you change to the double wall pipe the outside skin of the dvl will be much cooler and won't conduct heat into the class a skin. This may not be the fix all, but its fairly cheap alternative to try and like what others say, if it fails to stop the condensation, you'll have warmer flue gases anyway fixing a possible performance issue down the road.
Thanks for reply. I don’t know anything about about wood stoves. Double vs single. Is single inside my place or is all the pipe single? Is this a spring summer job? Probably for a professional? When you say cheap fix, what do you consider cheap? Ha. I attached new photo. Thanks again!
 

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We are going up in 3 weeks. I will give it a try. Thanks
I've always lived in a low humidity environment so I have never experienced it but it is possible that enough humidity and time could have the chimney insulation damp. Once insulation is damp it is a bear to dry. It still could be an ice dam situation. Is there a snow brake/diverter above the chimney? By the amount of snow present I'd install one if not.
 
I've always lived in a low humidity environment so I have never experienced it but it is possible that enough humidity and time could have the chimney insulation damp. Once insulation is damp it is a bear to dry. It still could be an ice dam situation. Is there a snow brake/diverter above the chimney? By the amount of snow present I'd install one if not.
We don’t have a diverter. I’ll look into one this spring. Before we bought the place, the cabin was left unheated all winter. It was only used summer and fall. Now when we are not there it is set to 50 with no issues. At 70 we get the dripping. Problem we have is there are so few people in the area who do this type of work. I guess a number have retired and not many going into the profession.
 
Thanks for reply. I don’t know anything about about wood stoves. Double vs single. Is single inside my place or is all the pipe single? Is this a spring summer job? Probably for a professional? When you say cheap fix, what do you consider cheap? Ha. I attached new photo. Thanks again!
It appears to be single wall. Being that you aren't running the stove I dont know that changing stove pipe would help.
 
The interior black ceiling plate should decorative. I'd unscrew it as well and see if you can inspect the interior roof penetration. This could be a situation where you have a small leak un-associated with the chimney. The water just found an easy way to exit
 
We don’t have a diverter. I’ll look into one this spring. Before we bought the place, the cabin was left unheated all winter. It was only used summer and fall. Now when we are not there it is set to 50 with no issues. At 70 we get the dripping. Problem we have is there are so few people in the area who do this type of work. I guess a number have retired and not many going into the profession.
I know what you mean trying to get people out to do work. I live an hour from town and another 10 miles of dirt road from the highway. I can rarely get folks that want to come out and do work. It doesn't appear that you will be on the roof until May or June so there is a lot of internal inspections that can occur until then. I'd remove that plate and see what is happening. If that doesn't reveal anything I'd consider taking down the internal stove pipe and see where the drip is coming from.
 
I would see if a dehumidifier inside would make any difference. If you could keep the humidity lower while you are there it might help some. What is the heat source? Any unvented gas appliances will contribute significant moisture to the air.
 
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Here are photos of condensation and better outdoor photos.
 

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It doesn't appear to be flashed correctly? Not being able to see it up close but it appears that they nailed flashing to the roof then shingled over the top.
 
Yeah, that last shot looks wrong. The flashing should be on top of the shingles on the bottom. The way they did it any moisture coming off the flashing cone is going to flow under the shingles.
 
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Yeah, that last shot looks wrong. Any moisture coming off the flashing cone is going to flow under the shingles. The flashing should be on top of the shingles on the bottom.
Thanks for reply. We were told that shingle over flashing was for ascetics. The leak is definitely coming down pipe. Even if flashing shouldn’t be shingled on bottom, wouldn’t leak be coming from another area?

Would flashing issue only be intermittent based on indoor temperature?
 
Thanks for reply. We were told that shingle over flashing was for ascetics. The leak is definitely coming down pipe. Even if flashing shouldn’t be shingled on bottom, wouldn’t leak be coming from another area?

Would flashing issue only be intermittent based on indoor temperature?
Aesthetics in this case gets trumped by function. You don't want moisture going under shingles. Whether this is the core of the problem I can't say. This still could be a condensation issue of a cold pipe in a warm interior.
Perhaps @Hogwildz has some thoughts.