Maintaining 6-inch stove pipe clearance through wall cutout

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Starfish Prime

New Member
Sep 28, 2022
5
Eastern Ontario
For several days now I've been trying to gather information on how to go about our wood stove (Pacific Energy Alderlea T5) install using correct practices.

If anything I've understood along the way is wildly unsafe or just inaccurate, please let me know.

We'll be venting through an exterior wall to a manufactured chimney. My understanding is that the stove pipe should never go through the wall, it's the insulated chimney that does. What I'm trying to wrap my head around is the necessity for a 6" clearance to the stove pipe where the pipe meets the chimney on the interior side of the wall. If no combustibles can be within 6" of the stove pipe, then the hole in the drywall needs to be a minimum of 18" in diameter (3" radius for the stove pipe, plus another 6", so a 9" radius) and no wood studs can lie within that cavity either. Is that correct? If so, then any framing done to support the opening in the wall needs to be done with metal studs and either the hole needs to be big (18"), or drywall needs to be replaced with a non-combustible surface...like cement board?

I have a wall thimble meant for 6" insulated chimney, but if the opening in the drywall is just big enough to screw the thimble to it then the 6" clearance won't be met. Right?
 
Check the specifications for your wall thimble. Where it passes thru the wall, the requirements for CTC are 2”. The Class A within the thimble will extend into the living space far enough that the 6” CTC for DW connector pipe only comes into play with regards to adjacent side walls or the ceiling.
 
Thanks DAKSY. I looked up the instructions for my wall thimble last night and saw that it only requires 2” of air space. I’m still not clear on what other pieces I would need for the wall pass-through. The stove pipe will attach right to the chimney, the chimney tee will get mounted within the thimble and the support bracket attached to the exterior wall keeps it in place. I think I need some kind of decorative ring to cover the gap between the 10” opening of the thimble and the outer wall of the stove pipe(6 1/4”).
 
Thanks DAKSY. I looked up the instructions for my wall thimble last night and saw that it only requires 2” of air space. I’m still not clear on what other pieces I would need for the wall pass-through. The stove pipe will attach right to the chimney, the chimney tee will get mounted within the thimble and the support bracket attached to the exterior wall keeps it in place. I think I need some kind of decorative ring to cover the gap between the 10” opening of the thimble and the outer wall of the stove pipe(6 1/4”).
You need a wall passthrough or thimble kit made by the manufacturer of your chimney pipe. From there just follow the directions