Clearance to Combustibles Measured Through Non-Combustibles

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pkay

New Member
May 22, 2024
2
Northeast Ohio
I have a specific question about measuring the minimum clearance to combustibles from wood stoves.

The question is this: when you have a wall which has a non-combustible surface layered directly on top of a combustible surface (no air space in between), is the clearance measured to the outer, non-combustible surface or is it measured through the non-combustible material to the combustible material behind it, as if the non-combustible wasn't there?

For example: a stove has a rear clearance of 10". The construction of the wall behind the stove is wood studs, 1/2" drywall on the studs, and 1" brick veneer on the drywall. Is the 10" clearance measured through the brick veneer to the drywall behind, thereby putting the stove 9" from the outer surface of the brick, or is it measured to the outer surface of the brick veneer, placing the stove 10" from the outer surface of the brick?

I've looked up a bunch of threads on the subject but through the years there seems to be differing opinions/final answers. I am familiar with NFPA 211. Is there an official source for the answer to this question one way or another?
 
I have a specific question about measuring the minimum clearance to combustibles from wood stoves.

The question is this: when you have a wall which has a non-combustible surface layered directly on top of a combustible surface (no air space in between), is the clearance measured to the outer, non-combustible surface or is it measured through the non-combustible material to the combustible material behind it, as if the non-combustible wasn't there?

For example: a stove has a rear clearance of 10". The construction of the wall behind the stove is wood studs, 1/2" drywall on the studs, and 1" brick veneer on the drywall. Is the 10" clearance measured through the brick veneer to the drywall behind, thereby putting the stove 9" from the outer surface of the brick, or is it measured to the outer surface of the brick veneer, placing the stove 10" from the outer surface of the brick?

I've looked up a bunch of threads on the subject but through the years there seems to be differing opinions/final answers. I am familiar with NFPA 211. Is there an official source for the answer to this question one way or another?
Nfpa is only the official source if your stove is unlisted. If your stove is listen the manual is the official source. But generally it is measured to the nearest combustible. But I would also strongly recommend against setting the stove at the absolute minimum
 
To be clear, it is measured through any surface non-combustible to the nearest combustible behind it.
 
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I have no problem with an install that meets or exceeds those requirements. So you can go right to the minimum. Or more, your choice.
 
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I have no problem with an install that meets or exceeds those requirements. So you can go right to the minimum. Or more, your choice.
True but if set at the absolute minimum pay close attention because stove move backwards over time in most cases
 
This is especially true for radiant stoves. I gave our F400 an extra 2-3" corner clearance and the wall behind it still got hotter than I wanted to see (160º) when the stove was being pushed for heat. The convective design of the T6 is the opposite.