Reframe for wood burning insert - is wood too flammable??

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CCove

New Member
Mar 31, 2023
1
28786
Hello,
We have an old stone fireplace that was cut directly into the wall (poorly done).
We smashed out the top half to cover with cement board and make it less obtrusive.
We put in new heat resistant cement in some holes and to level the top.
Then we framed with wood so we can add on the cement board.
We plan on putting a galvanized pipe and an insert into the fireplace.

Is it dangerous to leave the wood exposed under the cement board? There will be no direct flame however their is a large gap in the cement where the heat will rise and be on the exposed wood. Thoughts or how to block this if it's an issue? In photo red circle is where the heat will come up onto wood. Really big gap to try and fill, rather not if possible.

Thank you -

fireplace.jpeg
 
With an insulated liner connected to the insert it should be ok. What insert is going to be installed?
 
Hello,
We have an old stone fireplace that was cut directly into the wall (poorly done).
We smashed out the top half to cover with cement board and make it less obtrusive.
We put in new heat resistant cement in some holes and to level the top.
Then we framed with wood so we can add on the cement board.
We plan on putting a galvanized pipe and an insert into the fireplace.

Is it dangerous to leave the wood exposed under the cement board? There will be no direct flame however their is a large gap in the cement where the heat will rise and be on the exposed wood. Thoughts or how to block this if it's an issue? In photo red circle is where the heat will come up onto wood. Really big gap to try and fill, rather not if possible.

Thank you -

View attachment 311621
No galvanized pipe can be used at all you need a full insulated liner from the stove to the top of the chimney.

There is also no benifit in using cement board there with wood framing behind it. As long as the holes were patched properly and the liner is insulated wood and drywall will be fine.
 
Good point, definitely not as a liner. It's unclear if the OP meant galvanized chimney pipe on top.
 
I know its not needed with an insulated liner, but metal studs there would have been some additional insurance.
 
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Also, a block off plate would help prevent heat from coming up (and would give more of the heat output of the insert into the room rather than up the chimney to the top).