Corner Wood Stove Near Insulated Concrete Form Walls

[MissInformed]

Looking for any experience other posters may have with wood stoves near insulated concrete walls. I bought a place and a stove and feel ready to move forward with installation of the stove. I don't want to rush into it though. I'd rather slow play things than end up backtracking. The stove is not the planned primary heat source, but will need to be used for a time. Our concrete walls were poured as a monolithic pour inside insulated forms. We are the 3rd owners on this unfinished project so I do not have info from original manufacturer of the wall system.

I think clearance will be a non-issue as we have plenty of floor space and room to work with. The stove will be in a corner, although it is not in a 90 degree corner (closer to 135 degrees). My question is primary one of which materials are best used and in which order. If I want to put up a decorative stone/brick mantel area when the drywall goes up. What should go behind it and in what order? I want to protect the insulated form integrity while also creating an area that holds heat well and safely.

 

[Doc C]

I would treat the insulated part of the form as flammable. With that being said I would figure out you would like to use for your decorative wall that is not flammable and space it off the wall 1”. Rutland makes a spacer kit for this reason also you can make your own.

For instance if you are using tile you can use the spacers to get you out away from the wall at least 1” and then attach concrete board to the spacers and tile with thin set over that.

If you let us know what you would like to use we can give you some ideas how to achieve it safely.

 

[cjgoode]

Treat the wall as a combustible material because of the insulation and you will be fine. I picked the Osburn 2200 because it has the largest bay window I could find for our NC house. Turns out it also is certified for a trailer and has close clearances in the back to combustible material. So first we taped where the stove would have to go on the floor with clearances + extra safety margin, also not a 90 degree corner, and also not our only heat source. Next got the stove (Luckily a used one came up on CL near me in Fl, what are the chances of that). Built the wood part of the hearth extension and sat it up on their. Liked it so we put in the flue sat it on a cement board proper distance in front and fired it up. Monitored how hot the combustible wood behind it got and no problems. Now to finish the hearth with stone, and I also will remove the wood log interior and make it stone for looks and heat retention not to reduce the clearance distance. So even though I will have stone I will still be 4 inches further then required to combustible materials. I took the minimum as just that minimum and added more for extra safety. Your stove should have minimum clearance from all sides and angles from the rear of your model. Mine was 13 inches in the rear and 10 inches from the corner and 18 inches from the single wall pipe. Turns out the 18 inches from the single wall pipe forces it out more then 13 inches in the rear because the pipe is in the rear of the stove. I could have done double wall if I wanted to go close, but like you I had plenty of room to pull it out. Yes we have a gas fire place in the same room also good hear source for those slightly chilly days or just ambiance.

 

[Woodwringer]

If the insulation is currently exposed, it should be covered by 1/2 inch or thicker drywall, whether there is a stove or not. Where you place your stove, you should have an air space of at least 1 inch between the drywall and the heat barrier that you choose. Cement backer board covered by tile is a good option. The air space should be open at the top, sides, and bottom if possible so that room air can easily circulate behind the heat barrier.

 

[Squisher]

If the insulation is currently exposed, it should be covered by 1/2 inch or thicker drywall, whether there is a stove or not. Where you place your stove, you should have an air space of at least 1 inch between the drywall and the heat barrier that you choose. Cement backer board covered by tile is a good option. The air space should be open at the top, sides, and bottom if possible so that room air can easily circulate behind the heat barrier.

You only need to do all this shielding if you're looking to reduce clearances. If the stated clearances for the appliance are met in full no shielding or any special construction is required.

 

[Woodwringer]

The reason for the drywall is that any flammable foam insulation is not allowed to be left exposed in the interior of a house, because the foam releases toxic fumes when it burns. It has nothing to do with the stove.

 

[Squisher]

The reason for the drywall is that any flammable foam insulation is not allowed to be left exposed in the interior of a house, because the foam releases toxic fumes when it burns. It has nothing to do with the stove.

Which is why I only addressed the shielding you were talking about. 1"spaced off shielding is only required if you are looking to reduce the clearance requirements of the stove.

 

[SuperJ]

If I could have my stove re-installed I'd ask them to have a bigger clearance. The stove is about an 1" beyond minimum, but now I'm thinking of doing some stone or tiles on the wall and may run into clearance issues. Would've been nice to have the stove out another couple inches for future flexibility.

And the posts above are correct about foam insulation, it must be covered with drywall or some other material that meets a certain flammability spec. The minimum clearances are acceptable for a flammable material like foam (at least in my area).

 

[bholler]

If I could have my stove re-installed I'd ask them to have a bigger clearance. The stove is about an 1" beyond minimum, but now I'm thinking of doing some stone or tiles on the wall and may run into clearance issues. Would've been nice to have the stove out another couple inches for future flexibility.

And the posts above are correct about foam insulation, it must be covered with drywall or some other material that meets a certain flammability spec. The minimum clearances are acceptable for a flammable material like foam (at least in my area).

The stone or tile wont change the clearances to combustimbles. But yes extra clearance is never a bad idea