Fireplace -- how to remedy a rusted firebox liner

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soundofsilence

New Member
Mar 28, 2022
25
Chicagoland
Hi all, my wife and I purchased a house that was built in the 50s. I'm not sure if the wood burning fireplace dates that far back. Our local fire department did an inspection and said the firebox liner was rusted and cracked and that we could not safely use the fireplace. They said the chimney was in good shape, but they didn't actually go on the roof -- I wonder if the rusted liner indicates water leaking into the chimney. We would like to get this resolved so we can start using the fireplace.

I'm attaching some pictures of the damage. One suggestion from our local FD was to remove the liner and line the entire firebox with new ceramic firebricks. I'm curious if this is our best option. It does seem like this would be a good aesthetic solution. I assume we'd still need a new flue damper as well? Any suggestions as far as whether this is a DIY job or how much we should expect to pay to have this done professionally would be much appreciated.

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bholler

Chimney sweep
Staff member
Jan 14, 2014
28,701
central pa
Hi all, my wife and I purchased a house that was built in the 50s. I'm not sure if the wood burning fireplace dates that far back. Our local fire department did an inspection and said the firebox liner was rusted and cracked and that we could not safely use the fireplace. They said the chimney was in good shape, but they didn't actually go on the roof -- I wonder if the rusted liner indicates water leaking into the chimney. We would like to get this resolved so we can start using the fireplace.

I'm attaching some pictures of the damage. One suggestion from our local FD was to remove the liner and line the entire firebox with new ceramic firebricks. I'm curious if this is our best option. It does seem like this would be a good aesthetic solution. I assume we'd still need a new flue damper as well? Any suggestions as far as whether this is a DIY job or how much we should expect to pay to have this done professionally would be much appreciated.

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There are a few options.

1. Cut the old metal firebox out and replace it with a masonry one.

2. Take the masonry face off and replace the metal firebox with a new one if you can find one that fits.

3. Put in a gas or wood insert with a liner running out the top
 

soundofsilence

New Member
Mar 28, 2022
25
Chicagoland
Loving option 3, especially if we can kind of leave the liner as is, aside from cutting out a section for the flue liner.

Kind of concerned about how I would circulate air throughout the house, we have a large area on a slab on the far end of the house "behind" the fireplace ... but the house is only 3000 sq ft, so I assume it's doable.
 

begreen

Mooderator
Staff member
Nov 18, 2005
93,846
South Puget Sound, WA
3000 sq ft is a large home. If there are cathedral ceilings and/ or a lot of big windows, then that will be a challenge to heat with just the insert. If the slab is uninsulated it will suck heat out of the room.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,701
central pa
Just got my initial layout done on one after cutting out the box this morning

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soundofsilence

New Member
Mar 28, 2022
25
Chicagoland
3000 sq ft is a large home. If there are cathedral ceilings and/ or a lot of big windows, then that will be a challenge to heat with just the insert. If the slab is uninsulated it will suck heat out of the room.
It's a 1.5 story (partial 2nd floor) ranch, and the fireplace is placed in the middle of our home (which seems ideal). The area on the slab seems like an addition (the rest of the home has a crawlspace), and it has a cathedral ceiling that connects to the 2nd floor). From what I've read, we'd need:

1. probably the largest insert we can fit in the fireplace
2. a way to move some air from the room on the slab

Even then, we still might need to rely on the furnace to supplement heating the far end of the house (over the slab). That room stays pretty cool in the winter, but assuming we closed off ducts to the main area of the house (once we got the insert up and running) perhaps that would solve the problem and the furnace would only be used to heat that particular area.

Long-term, maybe we figure out a solution. We don't have a second chimney, but maybe there's a solution I don't know about to heat that area above the slab.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,701
central pa
Was it necessary to cut out the box (liner)? If there's an advantage I'd be willing to cut mine out.
To build a new masonry firebox. Yes absolutely nessecary. For an insert no
 

begreen

Mooderator
Staff member
Nov 18, 2005
93,846
South Puget Sound, WA
It's a 1.5 story (partial 2nd floor) ranch, and the fireplace is placed in the middle of our home (which seems ideal). The area on the slab seems like an addition (the rest of the home has a crawlspace), and it has a cathedral ceiling that connects to the 2nd floor). From what I've read, we'd need:

1. probably the largest insert we can fit in the fireplace
2. a way to move some air from the room on the slab

Even then, we still might need to rely on the furnace to supplement heating the far end of the house (over the slab). That room stays pretty cool in the winter, but assuming we closed off ducts to the main area of the house (once we got the insert up and running) perhaps that would solve the problem and the furnace would only be used to heat that particular area.

Long-term, maybe we figure out a solution. We don't have a second chimney, but maybe there's a solution I don't know about to heat that area above the slab.
Yes, look at ~3 cu ft inserts from Lopi, Regency, PE, Osburn, etc. The slab area will be easier to heat if the floor gets an insulated covering. Even 1/2" of foam flooring will make a notable difference. Eventually, maybe add a freestanding stove to this area with its own chimney.

It's not a good idea to bock off vents in the HVAC. This can unbalance the system and can lead to premature blower failure.
 

EbS-P

Minister of Fire
Jan 19, 2019
2,686
SE North Carolina
Loving option 3, especially if we can kind of leave the liner as is, aside from cutting out a section for the flue liner.

Kind of concerned about how I would circulate air throughout the house, we have a large area on a slab on the far end of the house "behind" the fireplace ... but the house is only 3000 sq ft, so I assume it's doable.
Look into the tax credit for units with 75% and greater HHV efficiency. But I would still consider units that don’t qualify. I’m handy and did a DIY insert install. It was cheaper to get a cheaper unit that didn’t qualify than it was to get the tax credit.

I’d look at a mini split for that room. Zoned heating is nice.
 

soundofsilence

New Member
Mar 28, 2022
25
Chicagoland
Yes, look at ~3 cu ft inserts from Lopi, Regency, PE, Osburn, etc. The slab area will be easier to heat if the floor gets an insulated covering. Even 1/2" of foam flooring will make a notable difference. Eventually, maybe add a freestanding stove to this area with its own chimney.

It's not a good idea to bock off vents in the HVAC. This can unbalance the system and can lead to premature blower failure.
Thanks for all the feedback. The slab area has wood floors
Look into the tax credit for units with 75% and greater HHV efficiency. But I would still consider units that don’t qualify. I’m handy and did a DIY insert install. It was cheaper to get a cheaper unit that didn’t qualify than it was to get the tax credit.

I’d look at a mini split for that room. Zoned heating is nice.
Good tips, thanks. I just installed a MrCool 24k DIY mini split in my 36x24 garage last year -- we actually had a compressor failure over the winter, so although I have to reinstall they provided a full warranty replacement.

Do you have a pic of your insert?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,701
central pa
Done with this job for the day

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EbS-P

Minister of Fire
Jan 19, 2019
2,686
SE North Carolina
Thanks for all the feedback. The slab area has wood floors

Good tips, thanks. I just installed a MrCool 24k DIY mini split in my 36x24 garage last year -- we actually had a compressor failure over the winter, so although I have to reinstall they provided a full warranty replacement.

Do you have a pic of your insert?
It’s a Drolet 1800i. I got the kit with 25’ liner from Costco. I added insulation wrap. Total cost was 2000$. In august. They have gone up since then.

I chose not to install the surround. Reason’s being it makes it look bigger. I set the stove all the way back so I don’t need floor ember protection. And I had to add a damper. Ideally when I have time I will add a blockoff plate and trim and drill piece of single wall Stove pipe to hide the liner.

This is a second living space for now (it’s a walk out basement portion of which was a garage) and the second stove. Looks weren’t that important. Price was all I was buy on. Basement will get a mr cool diy mini split soon.

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stoveliker

Minister of Fire
Nov 17, 2019
4,590
Long Island NY
It's not a good idea to bock off vents in the HVAC. This can unbalance the system and can lead to premature blower failure.

It also increases leakage of heated air because of the higher pressure in the ducts.

I second the minisplit advice.