Wood stove hearth question

[ToltingColtAcres]

I've been in the process of doing some remodeling at my 300 y/o house and have demoed all the walls down to the studs in the room where the wood stove is located.

The hearth where my Jotul was installed is in a corner. The base consists of slate tiles installed with flexbond on top of concrete board which is screwed down to the plywood underlayment.

The corner walls were wood planks nailed into wood studs. Two concrete boards were installed about 1.5" in front of the wood walls with spacers, and then slate tiles mortared onto the concrete board. The concrete boards extended up about 5 feet.

Now that everything is down to studs, I have a question on rebuilding the corner walls of the hearth.

Can I simply attach concrete boards to the wood studs, and then tile over them, or do I need to create another "wall in front of the wall"?

Originally as it was explained to me the "wall in front of the wall" was necessary to allow air to flow between the concrete board and the wood wall because the wood wall was flammable. Since the "new" wall will be non-flammable, I'm curious if all the extra work is necessary to create that air-space.

Thanks!

 

[bholler]

I've been in the process of doing some remodeling at my 300 y/o house and have demoed all the walls down to the studs in the room where the wood stove is located.

The hearth where my Jotul was installed is in a corner. The base consists of slate tiles installed with flexbond on top of concrete board which is screwed down to the plywood underlayment.

The corner walls were wood planks nailed into wood studs. Two concrete boards were installed about 1.5" in front of the wood walls with spacers, and then slate tiles mortared onto the concrete board. The concrete boards extended up about 5 feet.

Now that everything is down to studs, I have a question on rebuilding the corner walls of the hearth.

Can I simply attach concrete boards to the wood studs, and then tile over them, or do I need to create another "wall in front of the wall"?

Originally as it was explained to me the "wall in front of the wall" was necessary to allow air to flow between the concrete board and the wood wall because the wood wall was flammable. Since the "new" wall will be non-flammable, I'm curious if all the extra work is necessary to create that air-space.

Thanks!

The new wall is still going on wood studs right? So it is still flammable. What stove is this for?

 

[Dustin]

If your stove is within its clearance requirements as listed in the manual, you need not have a non combustible wall behind it. You can just do concrete board to the studs and tile over it, it’s just for looks.

If you’re not going to follow the clearance requirements (Stove or stove pipe) you’ll have to have a protected wall with airspace.

 

[ToltingColtAcres]

The new wall is still going on wood studs right? So it is still flammable. What stove is this for?

Jotul F55

If your stove is within its clearance requirements as listed in the manual, you need not have a non combustible wall behind it. You can just do concrete board to the studs and tile over it, it’s just for looks.

Yes, I do have the clearance, as I use double-wall stove pipe and a flue connector, so my distance to the walls is only 12" from the corners. However, in retrospect, your reply gave me the thought: what if I replace the stove some day with a different model? With a different stove, I may not be so lucky with clearances.

So airspace it is. Now the question is: how deep does the airspace have to be? It was (roughly) 3/4" from the back of the concrete board to the face of the wood wall. If I hang 1/4" concrete board where the wood wall was, what distance do I need to the back of the concrete board in front of it?

Thanks for the replies, gents.

 

[bholler]

Jotul F55



Yes, I do have the clearance, as I use double-wall stove pipe and a flue connector, so my distance to the walls is only 12" from the corners. However, in retrospect, your reply gave me the thought: what if I replace the stove some day with a different model? With a different stove, I may not be so lucky with clearances.

So airspace it is. Now the question is: how deep does the airspace have to be? It was (roughly) 3/4" from the back of the concrete board to the face of the wood wall. If I hang 1/4" concrete board where the wood wall was, what distance do I need to the back of the concrete board in front of it?

Thanks for the replies, gents.

If you have the required clearances you don't need the airspace.

 

[mcdougy]

You could attach this to your wood studs, then your concrete board

 

[Nigel459]

Jotul F55



Yes, I do have the clearance, as I use double-wall stove pipe and a flue connector, so my distance to the walls is only 12" from the corners. However, in retrospect, your reply gave me the thought: what if I replace the stove some day with a different model? With a different stove, I may not be so lucky with clearances.

So airspace it is. Now the question is: how deep does the airspace have to be? It was (roughly) 3/4" from the back of the concrete board to the face of the wood wall. If I hang 1/4" concrete board where the wood wall was, what distance do I need to the back of the concrete board in front of it?

Thanks for the replies, gents.

To answer that directly, for a shield to be effective I think it’s min 3/4” of airspace IIRC. That’s all around including underneath to allow flow. Re: the concrete board wall, the listed clearances are “to combustibles” so if you replace the wood wall with concrete board now your studs are the nearest combustible.

 

[bholler]

To answer that directly, for a shield to be effective I think it’s min 3/4” of airspace IIRC. That’s all around including underneath to allow flow. Re: the concrete board wall, the listed clearances are “to combustibles” so if you replace the wood wall with concrete board now your studs are the nearest combustible.

It is 1" for a proper nfpa ventilated wall sheilds. But that isn't needed if clearances are already met

 

[firefighterjake]

It's all about distance to combustibles and meeting the manufacturer specifications. In my own hearth I actually exceeded the clearances by a couple of inches and just had painted dry wall behind my stove. However, the wall did get pretty warm to the touch and my wife felt better when I ended up removing the dry wall, installing cement board directly to the studs and applying ceramic tile -- truthfully it didn't do a whole lot in terms of clearances, nor did it make an insulating air gap -- but my wife felt better knowing there was no paint or paper on dry wall which could potentially ignite and for me it was a relatively easy project and made the hearth look nicer (but that said . . . in the end it was still all about meeting or exceeding the manufacturer's clearance requirements which I actually could do before my little project.)