Clearance problem

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Greenhorn

New Member
Oct 26, 2014
8
Colorado
Hello everyone, I recently bought a house that is almost a hundred years old. At some point a wood stove was installed using triple wall pipe through the roof. It stops about three feet above the stove and turns into single wall. The single wall 45's away from triple wall and then 45's into stove (corner install). Behind stove is 1/2" gypsum board then 1/2" dura rock. The clearance of the wood stove to dura rock is 15" (englander NC30). Problem is the single wall pipe is only 5" from dura rock where it 45's into triple wall pipe. Any ideas on a remedy other then redoing the roof penetration which would allow triple wall to move away from walls?
 
I don't really have a clear picture of what your problem is,
but it sure sounds like double-wall connector pipe might be
a viable solution.
 
Thank you for the response. Don't laugh to hard at the picture but I ran out of time and money this year, mainly time as winter has sent in. The three wall pipe is supported in two places above the ceiling but I added the brackets below just for now until I can finish the walls with stone and fabricate something a little more eye pleasing. I started a fire last night and everything went well except for the new stove burn off smell. The wall behind the single wall elbow never got to hot to touch but I think I will still add the double wall elbow per your advise. Now I need to find one, all the wood stove & fireplace stores say that I have to go double all the way to the stove and not just the elbow. Does this sound right?
 

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Wow. That's not the prettiest install around.
Yes, if you change to double wall, it's ALL gotta be double wall
& it all has to come from one manufacturer.
 
No not at all, it looks like when they originally installed the pipe they miss measured the roof penetration. So I had to make do this year until I can fix the roof next spring which should allow me to bring the pipe straight down into the stove. Its one of those deals where I started replacing just the stove and then took a closer look and found all kinds of problems.
 
It is very important to know what type of chimney pipe this is. If it's old school air-cooled triple wall it is not suitable for wood stove operation. If it is something like DuraPlus triple wall then that is ok. There should be a label on the pipe at some point. If not, peer into the end of the pipe and take a picture. If all you see are air separations between the pipe layers, it is not class A high-temp pipe.
 
It is very important to know what type of chimney pipe this is. If it's old school air-cooled triple wall it is not suitable for wood stove operation. If it is something like DuraPlus triple wall then that is ok. There should be a label on the pipe at some point. If not, peer into the end of the pipe and take a picture. If all you see are air separations between the pipe layers, it is not class A high-temp pipe.

The Tag says Dura Chimney, Catalog NO 6DCR-T, UL rated by Simpson Duravent. When I remove the adapter plate from the bottom it is definitely air cooled.
 
The Tag says Dura Chimney, Catalog NO 6DCR-T, UL rated by Simpson Duravent. When I remove the adapter plate from the bottom it is definitely air cooled.

Being that I am new to all of this can I ask why this pipe is not suitable. Is it because of the Class A rating alone or is it a fire hazard, or both. I did find this on the internet:

There are two types of class A chimney pipe:

  • Solid-packed chimney. These pipes have smaller inner diameters (usually ranging from 5 inches to 8 inches) that have some insulation, either double-wall (like Simpson Dura-Vent DuraTech pipe) or triple-wall (like Simpson Dura-Vent DuraPlus pipe). These pipes use fiberglass or ceramic insulation to stay cooler on the outside and have a 2 inch clearance to combustibles.
  • Air-cooled chimney. These pipes have larger inner diameters (usually ranging from 8 inches to 24 inches) that have no insulation. An example of this kind of class A pipe is the FMI chimney pipe that is required for use with FMI and Vantage Hearth manufactured fireplaces. As the name implies, these pipes rely on the air circulating within them to keep the outer wall cooler and also have a 2 inch clearance to combustibles.
If its on the internet it must be true (joking).......would much rather listen to you guys.
 

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DuraChimney is not rated for woodstove use. It is not class A pipe and has a lower temperature rating. I won't say it is deadly unsafe, but it won't pass inspection or insurance requirements. It's lower temp rating is meant primarily for zero clearance fireplace use.
 
This is getting better by the minute. Well I guess its better to find out now before the house burned down. It pains me to ask but if I keep a close eye on it and burn at lower temps can I at least get through the winter. I have ripped out all the walls they had hiding the pipe and it is exposed all the way to the roof. I just need to make it to next spring before I can spend the money on new pipe and all the other repairs.
 
The main things to watch if using this pipe temporarily are clearances, flue temps and creosote build up. It must have at least 2" clearance all the way up through the the house. More is better. With a chimney fire, or too high flue temps all bets are off. If it were my house I'd replace it or consider not relying on wood for heat this season.
 
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It will probably be ok but i cant tell you that it is ok to use it that way because it is definitely not made for that application. If you are going to use it burn it normally if you burn it at low temps you will be making more creosote and have a larger potential for a chimney fire which is when you could get over the approved operating temps for that pipe. And yes i agree with begreen if it was mine i wouldn't use it either
 
Looking at the pricing now for new pipe. Will definitely be spring before I can replace it with the holidays coming on. Last night I never let the temp get over 450 degrees, the Dura Chimney never got to hot to touch. The hottest spot was right before it exited the roof and even then I could hold my hand to it without burning. Does 450 seem like a good temperature to operate at? Since this is not the correct pipe I'm thinking I should clean at least once a month
 
Like i said before if you are going to use it which i don't recommend you are best to burn it normally burning it cool will greatly increase your risk of a chimney fire. I beleive your pipe is rated to 1700 degrees which can easily be surpassed in a chimney fir but not with normal burning.
 
Wondering how Greenhorn did with this last year. I have a similar situation. Someone gave me an entire, unused Dura Chimney, with mounting hardware, cap, wall mounting bracket, tee.... exact part number as posted by Greenhorn. I want to put a wood stove in my garage and vent it horizontally out of the back of the stove, and up the outside wall. I'm leaning towards selling the stuff on craigslist and putting it towards a class-A chimney, but man, you'd think those things are lined with gold!
 
A couple caveats with the garage install. Be sure to check with the local inspecting authority. Wood stoves in garages are banned in a lot of jurisdictions. Some allow them but with caveats like it has to be on an 18" high platform. Check first. Also, modern stoves need a decent height flue/chimney, usually at least 15ft. This is sometime awkward with a garage install due to low roof height.
 
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