preparing old fireplace for small stove

[meagloth]

Hello everyone, happy new year. We are preparing our old fireplace to put a Vermont castings Aspen C3 in it and run the stovepipe up through what remains of the masonry chimney. The fireplace had been bricked up and today we opened it up and found many more bricks than we expected. Was a pain to bust them all out even with an air chisel, as you can see in pictures.

Once we got all the bricks out we could see that the concrete floor inside the firebox is not level but slopes up to the back of the fireplace, more than 1/2" from front to back. I am wondering about the best way to get it level for the wood stove. I would consider leaving it the way it is, but I have a big piece of soapstone from a kitchen countertop job I want to use as a hearth pad/pad extension. Right now I can't lay that down on un-level concrete. Should I bust out all the concrete and start from scratch?

 

[begreen]

Is that wood under the hearth? If so, that's not code, though less of an issue for a woodstove. The wood might just be from the form for the hearth that never got removed.
Can the back concrete be ground down to level it?
Watch the mantel clearances for the stove. It needs at least 8" from side trim and 22" above the stove.

 

[meagloth]

Is that wood under the hearth? If so, that's not code, though less of an issue for a woodstove. The wood might just be from the form for the hearth that never got removed.
Can the back concrete be ground down to level it?
Watch the mantel clearances for the stove. It needs at least 8" from side trim and 22" above the stove.

Yeah sure is wood directly underneath. I've seen similar in some videos, i think they used wood to make concrete form and left it?
I can try grinding the concrete with an angle grinder but im leery about how long it will take. Has anyone done something like that before?
I'm aware of the mantle and trim clearances and good to go. Whole mantle and trim may get replaced regardless though.

 

[begreen]

A half inch shouldn't take too long. It will be a dusty job for sure. Wear good eye, face, and breathing protection. A dust shroud on the grinder and the right grinding wheel help a lot.

 

[moresnow]

What about the entire chimney from fireplace floor to top? Professionally inspected? Verified safe for an insulated liner?
Before I exerted anymore energy.
I may have missed a prior post you already made on that topic.

 

[begreen]

What about the entire chimney from fireplace floor to top? Professionally inspected? Verified safe for an insulated liner?
Before I exerted anymore energy.
I may have missed a prior post you already made on that topic.

Yes, the chimney needs to be clean before putting in the liner. The point of the insulated liner is to make it zero clearance and safe but the chimney should be dry and sound.

 

[meagloth]

There's not much left of the chimney. It doesn't puncture the roof; was taken down by a previous owner, presumable due to water damage when the roof was redone. It goes about 2ft up into the attic and stops. The plan is to run double wall stove pipe for the first few feet in the masonry and then transition to class A chimney pipe up through the attic and roof.

 

[meagloth]

What about the entire chimney from fireplace floor to top? Professionally inspected? Verified safe for an insulated liner?
Before I exerted anymore energy.
I may have missed a prior post you already made on that topic.

To answer this directly there has been no inspection and there is no liner. The width of the chimney meets 6" clearance to combustibles for the double wall pipe.

 

[Eman85]

In my mind it would be easier to put some new concrete over the top of yours and level it instead of grinding what's there.

 

[meagloth]

In my mind it would be easier to put some new concrete over the top of yours and level it instead of grinding what's there.

yes it probably would but this would make for little clearance between the stove and the fireplace lintel, making it hard to install. It would have be a 2" step up from the floor to the hearth once I add the soapstone, which would look odd.

 

[begreen]

There's not much left of the chimney. It doesn't puncture the roof; was taken down by a previous owner, presumable due to water damage when the roof was redone. It goes about 2ft up into the attic and stops. The plan is to run double wall stove pipe for the first few feet in the masonry and then transition to class A chimney pipe up through the attic and roof.

The proper way to do this is to drop an insulated stainless liner down the chimney with a connector to the stove. An anchor plate is attached at the lopped off chimney top. The liner is supported at the anchor plate and from there transitions to class A chimney pipe up through the roof.

 

[meagloth]

I was able to get the concrete level with a combination of grinder disc and air chisel. Work would have been fast with the angle grinder but it made so much dust that about 10 seconds of grinding blinded my view utterly, and I had to stop and wait another 10-15 seconds for my dust collector to clear it. I took it all down to my laser level line, which is about an inch above the floor and about 1/2" higher than the black hearth extension.
After getting it level I checked my clearance and found that even after brining it all level I'm really pushing it on the clearance for the stove.

if I place my soapstone on the laser level line my opening will be about 24.5" tall. So the main body of the stove will technically fit but I won't be able to slide it in because of the stove pipe connecter. Even if I can take that off to get it in and put it back on, I'm not super happy with 1" of clearance between the top of the stove and the metal lintel/old mortar. I imagine it would get pretty toasty.
I thought about seeing if a mason could make it an arched opening, but I think my best option is to essentially move the lintel up on layer of bricks and remove the 3 bricks currently sitting on the lintel. My intuition says the best way to do this is to but a new piece of metal, grind out the grout, and insert the new lintel before removing the old one below it and subsequently the bricks. But the bricks are old and I'm curious for any advice.