Can I remove the brick lining my firebox permanently to make room for an insert?

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HoffDNA

New Member
Mar 20, 2023
6
CT
Hi all! Our firebox is very small and I'd like to put in a propane insert. I was wondering if I can remove the brick lining the firebox to make room for a larger insert. (I would hire an expert to do the removal.) Our central chimney is made of large cinderblocks and was built in 1998. Is the brick lining functional or just for looks?
Thanks for your help.
 
The brick liner is usually there to create the proper thickness for the masonry to be certified for a fire, it is all designed for support of the chimney above.
Inserts are tested and passed knowing that they will be installed in a properly built fireplace with the proper masonry clearance. By removing brick layers, you may be voiding the fireplace’s certification to have a fire within or an insert installed.
 
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With a gas insert being put in it probably wouldn't be a problem.
But there really should be a permanent sign placed on the back wall of the fireplace before the gas insert is installed that says the firebrick has been removed and the fireplace is not safe to burn in.
 
Thanks! Sounds like the answer is "maybe" and if it's acceptable then we need to alert future homeowners. Is there a way to find out how thick the masonry is? Any other considerations?
 
Thanks! Sounds like the answer is "maybe" and if it's acceptable then we need to alert future homeowners. Is there a way to find out how thick the masonry is? Any other considerations?
The answer really is maybe. It depends on the insert manufacturers instructions and the thickness of your masonry structure
 
How big is the current firebox and what size insert are you looking to Install? Is this more for ambiance or Heat output or a combination.? The experts here may know of other inserts that will fit in the current firebox and provide the results you are looking for it they are shared.
 
How do I find out the thickness of the structure behind a closed fireplace?
Long but small diameter masonry drill bit
 
Hi all! Our firebox is very small and I'd like to put in a propane insert. I was wondering if I can remove the brick lining the firebox to make room for a larger insert. (I would hire an expert to do the removal.) Our central chimney is made of large cinderblocks and was built in 1998. Is the brick lining functional or just for looks?
Thanks for your help.
What are the full fireplace interior dimensions? What propane fireplace inserts are being considered?
 
We are currently planning on a Heat&Glo Supreme 30" but that would seem very small. Even that size will stick out a bit from the fireplace because the minimum back width is about 20". It would serve as supplemental heat and ambiance.
The dimensions we have are:
front opening 32.5 w X 29.5 h
rear wall is 17" wide X 17" deep (only 13" wide at the back due to angled sides)

PS. You guys are the best!
 
It sounds like the goal is to go up to a 36" propane gas insert. Is that about right? How large of an area would it be heating?

Propane is an expensive fuel. Look at the most efficient heaters and make sure they can be converted to propane. Before doing any demolition, it might be good to do a cost analysis of what it would cost to run this insert for a winter.
 
Yes, I think a 35-36" would be preferable. If we can't, that's fine, I'm just checking our options.

Very good point! Yes, we have a very efficient heat pump we use as supplemental most of the time, but it doesn't work well when it gets down in the teens or below. So we're not expecting to use a ton of propane.
 
Is the stove room wide open to other rooms or somewhat closed off?

I'm going to move this thread to the gas forum for more targeted responses. The Heat&Glo Supreme 30" looks like a good choice. Modifying the fireplace will bring more questions. Make sure clearances are ok for the mantel if there is one.
 
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I'm saying test the thickness of the FP first by drilling a piolet hole were the gas line will go in, this will give an idea of the thickness without destroying the FP since most FP's are symmetrical and built with the house during construction, plus you have the hole started for the gas line
 
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It doesn't really matter that the room is wide open, I think, because we're only using it for supplemental heat... plus, we don't really have the option of making it a bigger insert anyway if the bricks can't be removed. Would you agree?

As for the pilot hole, do you mean just to find out the thickness of the brick? Isn't it necessary to know the entire thickness of the brick + space + masonry?
 
Two questions come to mind- does the present fireplace MFR (If its a zero clearance fireplace) allow a gas insert to be installed and if so, does the insert MFR let you modify the zc fp interior- some will, some do not. A couple of MFRs make a smaller insert Enviro E20, Regency was making the little E234, there are smaller inserts out there to get put in. Good luck.