Passing through stone chimney

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ady5008

Member
Oct 1, 2019
30
Central PA
I had posted a couple weeks ago about this but the thread kind of got off on a rabbit trail. The house is in the middle of major renovations right now. We would like to put a stove in this room, and vent it into the chimney where there will be a flexible liner. The existing flue is for a fireplace in the basement that is no longer in use. There's an old hole already there, but it's too small and much too close to the large beam and ceiling. Where should we put a new hole and what components would we need to make it both safe, and up to code? If we pass through 9 inches from the beam, I believe we would need double wall on the pass through, even though the beam is seperated from the thimble by stone right? Otherwise I'd use single wall with a heat shield from the elbow to the chimney. The beam sits in a pocket, it doesn't enter the flue. Or should we just pass through 18 inches below the beam and stick with single wall? Doing this wouldn't leave much stovepipe exposed in the room. The beam is about 7' over the floor. When putting the tee through a terracotta thimble, do you secure it to the thimble at all? The chimney wall is 18" thick, can we just connect straight stovepipe to the tee to get the length needed to pass through? If we do go with a double wall tee, do we need anything special to connect the tee to the flexible liner? Are the double wall liners any good? I heard they don't have titanium and the single walls with insulation are actually better.
 

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You will want a medium or heavy-duty, insulated, single-ply liner. Considering it is all non-combustible the tee snout can pass through the stone without insulation as long as it is 12" from the beam. A 7" clay tile thimble will keep it tidy and will allow the 6" tee snout to pass easily.

Watch the stovetop to ceiling requirement. Many require a minimum 84" ceiling.

Was there something cut through in the past? It looks like there might be a patch below and to the right of the existing hole.
 
You will want a medium or heavy-duty, insulated, single-ply liner. Considering it is all non-combustible the tee snout can pass through the stone without insulation as long as it is 12" from the beam. A 7" clay tile thimble will keep it tidy and will allow the 6" tee snout to pass easily.

So 12" because it's seperated by masonry? If we put the pipe in location 1 of the attached picture with a heat shield on the pipe outside the chimney we would be good? What about location 2, also with a heat shield? The floor joist above location 2 is touching the chimney in spots, but doesn't sit in a pocket like the big main beam. The flue is marked by the red lines, not much side to side room to work with.

Watch the stovetop to ceiling requirement. Many require a minimum 84" ceiling.

Was there something cut through in the past? It looks like there might be a patch below and to the right of the existing hole.
There looks to have been a shelf built into the chimney there originally. Perhaps to warm things? It appears that the right side of it was patched, maybe when the big stone above it started to crack, and then the rest was filled in at some point. I would like to preserve this if possible.
 

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Looks like either location would work if the stove is connected with double-wall stovepipe or shielded single wall. Position #2 provides a bit more vertical stove pipe off of the stove. I recommend using double-wall, especially if the chimney height is on the short side.
 
Looks like either location would work if the stove is connected with double-wall stovepipe or shielded single wall. Position #2 provides a bit more vertical stove pipe off of the stove. I recommend using double-wall, especially if the chimney height is on the short side.

I need to measure, but I'm guessing we have 25-30 feet from the floor of the living room to the top of the chimney. Is there anything special we need to do to connect a double wall tee to the flexible liner?
 
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You would be connecting to the end of the ss snout coming from the tee. That is single-wall ss pipe. Crimp that end and push it into the double-wall, female end.