Repair / replace masonry chimney and add insert or replace with new zero clearance fireplace?

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New Member
Oct 10, 2023
Columbus OH
I'd like to be able to burn wood for heat and ambiance in the living room. Currently my house (1970s) has a masonry fireplace built of block with a clay liner, wrapped in stucco. In addition to the fireplace / insert upgrade, we want to replace the stucco with cultured stone.

The chimney stack above the roofline isn't in good shape right now - it has crumbling block, missing mortar (some of the flue tile is exposed) and flashing, and cracks in the crown. My original plan was to rebuild the stack above the roofline, attach the cultured stone to the existing chimney block, then put in an insert and steel liner inside the tile.

The quote I received was $1,000 more ($7800 vs $6800, not incl the cultured stone) to replace the chimney from top to bottom before adding the cultured stone, which seems safer since I don't know the shape of the block in the main chimney

Now I am wondering about a third option: tear down the existing chimney and replace it with a new zero clearance fireplace instead. I don't see many discussions on this, so I'm not sure if this is doable? It seems like it might be cheaper than rebuilding with masonry just to buy an insert

Are there any benefits to masonry + an insert over a zero clearance in this situation? What option would you choose?
Is your chimney also used for an Oil or Gas furnace? If it is just the Fireplace, I would probably go the route of Removing the Chimney and go with free standing unit. You can use the cultured Stone inside for aesthetics. If you need to rebuild the Chimney for the furnace that changes things.
Just the fireplace

What type of contractor would I talk to if I want to investigate the replace with zero-clearance option?
I am guessing that I would need to work with a builder instead of a mason?

I have watched a lot of guides about how to retrofit a wood burning insert into an existing masonry chimney, but haven't found many about installing a zero clearance on an existing wall. Is it DIY if I am comfortable with framing or will it all need to be handled by someone who has knowledge about the specific fireplace model I choose?
Get a 2-3 masons to look at the fireplace and chimney to get an assessment range of the scope of repairs needed. Tell them that you intend to install a stainless steel liner for an insert so it's the structural integrity that's the main concern, not the flue tiles.

Part 2 - Yes, this can be DIY if one has the skills. Removing an old fireplace is a fairly easy, but dirty job if the mortar is old and weak. I did this with my son in 2 days. Installing a ZC is fairly straight forward if one pays attention to the details and has a good working plan in place before starting. The installation instructions for most ZC fireplaces are detailed. Pick out a couple favorites and download the installation manuals. Read them over carefully and ask questions where something is not clear. The cost will still be in the $8-10k range or higher. A less expensive option would be to install a freestanding wood stove.
Thanks for the insight on the ZC install.

This mason was the second who suggested at least a rebuild of the stack if not the whole chimney. And it looks like it might be a comparable price to a demo + ZC install anyway

I trust this mason to get the work done so I will probably have him rebuild w masonry - even if it will be overkill for the insert in the end. It would also let us burn wood for a season as well, or move the insert somewhere else and still have a working fireplace

Before they start, should I ask for any specific masonry work, like adding an exterior vent for air intake or for them to modify / remove the damper after they demo the existing chimney? I was planning to ask them to add new clay tile because its cheap, but is there a reason it would be better not to have the tile after I add an insert?
If the goal is to restore the operational functionality to the fireplace, then replacing the flue tile makes sense. What is the current clay tile ID? An optional outside air supply is up to you.

Are there any caveats with an insert install in this location? Some issues might be clearances to the mantel or side walls, a too shallow fireplace, an arched opening restricting choices, etc. How will the insert be used, 24/7 heat or occasional fires? If 24/7 heat, how large of an area would it be heating and how open is this area to the rest of the house?
During demo my mason found serious issues with the existing chimney - pieces of charred wood stuck in the flue, nonfunctional mortar (he didn't need the grinder for the top several layers of block), blackened siding insulation since the block was not thick enough, and a smoke shelf that was not exactly functional. Apparently codes weren't a big deal in the 60s...
Rather than take on the work to rebuild for open wood I had him just a structural block shell that I can use with a liner.

It's a large fireplace (29.5" tall, 34.5" wide, 26.5" deep, rectangle opening) so it looks like I can fit most of the inserts on the market. We live in central Ohio and will not be burning 24/7. The room is open, about 650sq ft and has entryways to both upstairs and downstairs so I believe it should be feasible to heat most of the house when we need to. We do have a furnace as well.

Still trying to decide between the Lopi large flush mount (with cat) or the Supreme Lumis 32. I'm leaning towards the Supreme - even though I dont get a tax credit it has a larger viewing area and firebox, and no cat to worry about. Also I believe the sliding install bracket may make it easier to connect to the liner than the welded collar on the Lopi? I'm close on the width clearances, is it a mistake to think I can self install?

For the liner I am planning on the Rockford 6" kit with insulation. Since there is no tile in my chimney and its a new block walls, I think the install should be pretty easy. My mason left a 10"x10" straight hole to the top. I will have to remove some additional material from where the old damper used to be but it looks like an angle grinder will do the trick.