Class A Chimney to Masonry Chimney question

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dlb stone

Member
Oct 21, 2019
9
Conestoga, PA
I have an odd situation where we have older brick masonry chimney exiting through the ridge near the gable. However, the chimney ends at the attic floor. We are installing a heritage hearthstone on our first floor. The plan is to use double wall stove pipe (Duravent DVL) to the second floor, transition to triple wall chimney pipe(Duraplus) pass through the attic floor and then?

Choice A - 90 into a thimble that would connect to a chimney liner we would install in side the last 6 ft or so. I am not sure that could be done, they don't make 90s in triple wall Duraplus. They do make 30s though. Or switch back to DVL, which has 90s and thimble connections. Not sure if either would be considered up to code.

Choice B - Continue straight through the slate roof and flash in. Then I would likely remove the old chimney if it's useless. Probably the simplest option, just don't want to give up on the old chimney yet.

Choice C - I could go through the stone wall level 1 and avoid problems, but not the best option.

The previous homeowner had fired clay thimbles through the 2nd floor and attic, and one that passed into chimney. He must of used stovepipe the whole way up, I think insurance made him take it out. He then left me his hunk of junk Wooddoctor OWB with a leaky water jacket.

Let me know what yall think. Thanks
 
Take your time and read previous threads on the topic and view a couple videos on chimney liner websites. This is a fairly common problem. There are special T fittings designed for where the thimble is. The T snout gets added once the liner has been dropped into the chimney and the T hole faces the thimble hole. In the attic they make transition plated to switch to class A chimney pipe. It bolts to the top of the chimney stub. The class A pipe would then go up through the roof. A special flashing will be needed if this goes through the ridge. If the attic is tall enough, another option may be to put a 30º offset to miss the ridge.

There are other important details in this install like making sure the thimble is safe and legal, insulating the liner, etc. Also, I strongly suggest using DuraTech instead of DuraPlus. It is a much better quality pipe and it requires a much smaller diameter hole in the roof. This may be helpful if an offset is planned.
 
Take your time and read previous threads on the topic and view a couple videos on chimney liner websites. This is a fairly common problem. There are special T fittings designed for where the thimble is. The T snout gets added once the liner has been dropped into the chimney and the T hole faces the thimble hole. In the attic they make transition plated to switch to class A chimney pipe. It bolts to the top of the chimney stub. The class A pipe would then go up through the roof. A special flashing will be needed if this goes through the ridge. If the attic is tall enough, another option may be to put a 30º offset to miss the ridge.

There are other important details in this install like making sure the thimble is safe and legal, insulating the liner, etc. Also, I strongly suggest using DuraTech instead of DuraPlus. It is a much better quality pipe and it requires a much smaller diameter hole in the roof. This may be helpful if an offset is planned.

I have seen the tee snouts and the transition plates. The question that remains is how do I 90 into the snout from the Class A pipe? The chimney was built over load bearing walls, I can't access it from the bottom, only from 90ing into it from the side. In this scenario I will be replacing the thimble, and insulating the liner. Do you understand what I am asking?
 
I have seen the tee snouts and the transition plates. The question that remains is how do I 90 into the snout from the Class A pipe? The chimney was built over load bearing walls, I can't access it from the bottom, only from 90ing into it from the side. In this scenario I will be replacing the thimble, and insulating the liner. Do you understand what I am asking?
You really can't 90 into the chimney in the attic.
 
I have seen the tee snouts and the transition plates. The question that remains is how do I 90 into the snout from the Class A pipe? The chimney was built over load bearing walls, I can't access it from the bottom, only from 90ing into it from the side. In this scenario I will be replacing the thimble, and insulating the liner. Do you understand what I am asking?
No, I don't understand. The class A is only up in the attic. There is no snout or 90º turn up there. There is only 6" liner down the chimney. The snout is attached after the liner is dropped into the chimney. It is attached through the thimble, as shown in the video.
 
Do you see any reason to keep the masonry chimney? Is there any scenario it could be used? I can take it down and slate it in, just wondering...
No I can't think of any
 
No, I don't understand. The class A is only up in the attic. There is no snout or 90º turn up there. There is only 6" liner down the chimney. The snout is attached after the liner is dropped into the chimney. It is attached through the thimble, as shown in the video.
The chimney is just built on the attic floor. We see it here pretty often. My old house had the remnants of chimneys that were built on wooden platforms. The masonry only started about 2' below the roofline
 
The chimney is just built on the attic floor. We see it here pretty often. My old house had the remnants of chimneys that were built on wooden platforms. The masonry only started about 2' below the roofline
Bizarre. What tied into this attic only chimney and how in those old places? Based on the description I would definitely just tear it out if necessary or relocate the stove to a better spot and install new all the way.
 
Bizarre. What tied into this attic only chimney and how in those old places? Based on the description I would definitely just tear it out if necessary or relocate the stove to the best spot.
Single wall pipe running up through the house from parlor stoves. Not safe at all. There was usually a bucket of water sitting next to the pipe for when the floor started to smoke. All of the old holes in our house were charred badly.
 
Single wall pipe running up through the house from parlor stoves. Not safe at all. There was usually a bucket of water sitting next to the pipe for when the floor started to smoke. All of the old holes in our house were charred badly.
:eek: wow, that is why we have fire code.