Wall Behind Stove, Insullation ok ?

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New Member
Mar 5, 2022
Need accurate guidance. In NJ USA, have a pellet Stove in a corner. in my basement. The pellet stove pipe connects through sheetrock that has Brick Veneer, in between studs, through a wall thimble, and into a masonry Chimney. Moisture got in from opening in exterior steps which has since been taken care of. However, sheetrock with veneer got wet and has begun to warp. I removed the sheetrock wall. I want to replace the wall now, but I want it to be to code 100%.

Currently there are wood studs with insulation, then some so
some space, then a cinder block wall, then an exterior Chimney. I plan to use cement board instead of sheetrock. I may just stucko it without brick Vaneers. Here are my questions:

1. Is it to code to have fiberglass insulation behind the cement board in between the studs ?

2. Are wood studs acceptable ?
3. Pellet Stove clearance through wall is only 3 inches.

Thank you.


Minister of Fire
Nov 17, 2019
Long Island NY
My set up has the stud wall offset from the concrete wall by a foot, but has a recessed space of 3*3 ft or so where the stove pipe goes thru. I.e. cut a piece of your stud wall out, connect the stud wall to the concrete wall with short 1 ft sections perpendicular to both, put the (non-combustible)aesthetics on the concrete that you want, and you're good to go.

So the pipe goes thru only the concrete wall, not thru the stud wall.
Yes, I lost a little of the insulation there.


Staff member
Nov 18, 2005
South Puget Sound, WA
As long as the stove's clearances are honored it will be code compliant. Remember, the clearances are to the nearest combustible, which in this case sounds like the wood wall studs.