What kind of thimble do i need?

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NorEaster603

New Member
Sep 29, 2022
33
NH
Hello, here is how my chimney guy left things after installing the new 6” stainless steel liner:
[Hearth.com] What kind of thimble do i need?

What do i need to buy to connect my stove pipe safely to this? It will be going through a completely non-combustible wall (steel studs, cement board, thin brick). The threads i’ve read are all about going through combustible walls to the outside. So how do i go through a non combustible wall into my masonry chimney’s liner?

Thanks!
 
Hello, here is how my chimney guy left things after installing the new 6” stainless steel liner:
View attachment 311243

What do i need to buy to connect my stove pipe safely to this? It will be going through a completely non-combustible wall (steel studs, cement board, thin brick). The threads i’ve read are all about going through combustible walls to the outside. So how do i go through a non combustible wall into my masonry chimney’s liner?

Thanks!
I would be contacting your chimney guy to get his advice.
 
Hello, here is how my chimney guy left things after installing the new 6” stainless steel liner:
View attachment 311243

What do i need to buy to connect my stove pipe safely to this? It will be going through a completely non-combustible wall (steel studs, cement board, thin brick). The threads i’ve read are all about going through combustible walls to the outside. So how do i go through a non combustible wall into my masonry chimney’s liner?

Thanks!
Is the wall you are going through going to be right against the chimney?
 
There will be a roughly 2” air gap between the chimney and framing. 2.5” metal studs, 1/2” cement board, and i’m guessing 1/2” thin brick so ~6” total
And how close is the framed wall we see in the background of that pic?
 
I would be contacting your chimney guy to get his advice.
He said something like “ they make a thing that looks like a trash can that fits on there then i’d be probably filling in around there with cement”. I don’t know what that means and i’m not keen on having him back to my house, so i’m asking advice here since I imagine I’m not the only person who has encountered this kind of installation situation.
And how close is the framed wall we see in the background of that pic?
That wall will be gone and replaced with metal stud framing (haven’t demolished the wood framing yet)
 
He said something like “ they make a thing that looks like a trash can that fits on there then i’d be probably filling in around there with cement”. I don’t know what that means and i’m not keen on having him back to my house, so i’m asking advice here since I imagine I’m not the only person who has encountered this kind of installation situation.

That wall will be gone and replaced with metal stud framing (haven’t demolished the wood framing yet)
If the wall is truly completely non-combustible you can just extend the stainless out of that wall
 
If the wall is truly completely non-combustible you can just extend the stainless out of that wall
So just insert the stovepipe into the liner? What about aesthetics, any kind of flange thing to cover the joint and hole in the finished brick?
 
So just insert the stovepipe into the liner? What about aesthetics, any kind of flange thing to cover the joint and hole in the finished brick?
Stainless needs to extend through the non-combustible wall into the room and de permanently attached. Yes you can use a trim ring and remember the male end of all joints face the stove
 
Stainless needs to extend through the non-combustible wall into the room and de permanently attached. Yes you can use a trim ring and remember the male end of all joints face the stove
Ok. Any representative images or articles you know of offhand? Really helps to be able to picture it…
 
 
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I wasn’t planning to but all the masonry adapters i see are for double wall…
You don't need a masonry adapter you just need a piece of stainless pipe and a trim plate
 
You don't need a masonry adapter you just need a piece of stainless pipe and a trim plate
Im having trouble picturing how this is all supposed to fit together. There is currently a piece of stainless pipe sticking out the wall. Do i need another stainless pipe? does it go inside the one currently there? At what point does the standard black stove pipe 90 degree attach to point the stovepipe down to the stove? I apologize for my ignorance but details matter here.
 
Im having trouble picturing how this is all supposed to fit together. There is currently a piece of stainless pipe sticking out the wall. Do i need another stainless pipe? does it go inside the one currently there? At what point does the standard black stove pipe 90 degree attach to point the stovepipe down to the stove? I apologize for my ignorance but details matter here.
Yes your current stainless sticks out of the chimney but you are putting a non combustible wall in and you need stainless through that. And no the extension will need to go over your current pipe which means you will probably need to crimp your current pipe so it fits inside the new one. It will then get riveted on and I usually hammer the crimps flat after doing that. Your black pipe can then attach to that
 
Yes your current stainless sticks out of the chimney but you are putting a non combustible wall in and you need stainless through that. And no the extension will need to go over your current pipe which means you will probably need to crimp your current pipe so it fits inside the new one. It will then get riveted on and I usually hammer the crimps flat after doing that. Your black pipe can then attach to that
Oh ok so it’s a matter of extending it out to where the finished wall surface will be. How far out should it be past the wall? like 2”?
 
Ok. And is there a crimp tool required to crimp the pipe or can i just go at it with pliers?
Yes a crimp. Tool is required unless you are very good at doing it with pliers it will look butchered
 
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Yes a crimp. Tool is required unless you are very good at doing it with pliers it will look butchered
Ok. Last question for now, and i really appreciate your responses! Is there any benefit or requirement to pack the area around that thimble with cement? Something like this from the article posted above:
[Hearth.com] What kind of thimble do i need?
 
What stove do you have, a new one or one that you've run on the chimney previously? That could influence how far you want the stainless to come out of the wall, I'd think..
Is that stainless a tee snout, or how is that connected to the liner?
He said something like “ they make a thing that looks like a trash can that fits on there then i’d be probably filling in around there with cement”. I don’t know what that means and i’m not keen on having him back to my house,
Yeah, I don't blame you. That sounds like a "crock"...a crock o' crap. 😆
So on Sunday I helped a friend who has a PE Vista install a flue damper. I was having trouble getting the tubes out, to remove the baffle board and install it through the flue exit of the stove. The guy, and a neighbor who came over, said "let's just take the pipe off and install it." I agreed. But when we put the pipe back on (connector pipe>90* elbow into tee connected to flex liner,) the tee snout was moving around. After the guy drilled new screw holes in the pipe sections, I saw that the tee snout was tilted down instead of up! So I have to go back out there in the next day or two to fix that before he'll be able to run the stove.
I begged out of helping him install the chimney, and he said his insurance wanted a "pro" doing it anyway. Based on what I saw (farm store snap-together connector pipe and farm store adjustable 90* elbow, and the way the pipe coming out of the masonry was moving around, I'm expecting to pull the trim ring and see no crock supporting the pipe. And it's a given that the dealer/installer stuck him with the flimsy lightweight liner, with no insulation. 😒 Some of these pros are some real cons. 😆
I already told the guy that we'll get it fixed enough to finish the season, then rip it out and do it right. I already have a mid-weight flex liner I'm not using that can go in there. Maybe some other pipe stuff as well, I'll have to look..
 
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hat stove do you have, a new one or one that you've run on the chimney previously? That could influence how far you want the stainless to come out of the wall, I'd think..
Is that stainless a tee snout, or how is that connected to the liner?
It is a new (display model that had one tiny burn allegedly) Nectre N550. Clearance to combustibles is 10” as per the label but i’m looking to put it around 7” since it’s 100% non-combustible wall.

That said, i’d rather not see the stainless portion, just the black stove pipe and trim ring. Based on Bhollers 1.5”-2” suggestion i think that’s possible. So my current plan is to get the metal framing in place and measure, then figure out my rough pipe length needed. Any comment on whether to pack the thimble with cement in a roughly 12” square supported by the framing?
 
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Is that stainless a tee snout, or how is that connected to the liner?
Yes that is the T from the stainless liner. Looks like he ran it through another piece of pipe that is cemented in place. Not sure if this is the “correct” way or not but for the money paid i sure hope so…