Liner Install - Need Advice Before Ordering Kit

[antlerman]

I'm working on getting my firebox ready in order to drop a new liner in my chimney and hook up my Hearthstone Hearthmount stove. I got a good deal on a used unit and now need to tackle the chimney.

I removed the old unit, which had a fan and would not heat the home without electricity running, and am now cutting the box to make room for the liner.

The chimney is concrete block from the basement floor, one level down from my install, all the way through the attic and the roof, with brick on the outside.

The pics that follow show how I've cut the firebox (not sure if that's the correct name - the large steel case installed at the time the chimney was built). I can fit a flexible liner through it, but would prefer solid pipe. My question is; Can I cut away more of the steel box? Do I need to be concerned about cutting too much? Any pipe I install will be at least 18" from the exterior of the metal box, and it is against concrete block.

 

[Mike.O]

I just installed a flex liner a few weeks ago (I don't have the metal surround in my fireplace, just a fire brick corbil and metal damper). As long as you accept the fact there's no going back after you start cutting the metal of the existing fireplace, you can pretty much have your way with it. I would look at it as this..... cut as much metal as needed and as little fire brick as necessary. Then install a block off plate after and seal any open spaces with fireproof insulation.

I don't know if there is a huge advantage to going straight vs flex. Flex is very easy to install. Make sure to get the insulation kit if you go flex.

 

[yooper08]

If you go with solid pipe, you're more than likely going to need some flex anyway to get from insert to the pipe. Flex will do just fine for the entire run, so I wouldn't over complicate that. That said, if you can clear flex through it and get it to where the flue collar of the insert will be, then you should be good to go.

 

[antlerman]

As it stands, and the pics show (though tough to see I'm sure) I've cut away quite a bit of the box. If I cut some more, then I could use solid insulated pipe all the way down. My concern was cutting too much away, but I think Mike O. addressed this when he said:
" Then install a block off plate after and seal any open spaces with fireproof insulation." However, I don't know what you mean Mike?

If you mean a plate that would be flush with the face of the stone wall, I don't intend to do that because the wood stove is tucked in behind the plane of the brick wall by about 4 inches, and doing so would mean lost heat from the stove that could have been inside the house.

Also, I need to be able to get in there and remove the piece on the bottom of the "T" in order to clean the chimney. Can I simply fabricate steel plates that surround the pipe on the "ceiling" of the firebox once it is installed? With insulation around that? Does that make sense to you guys?

 

[Mike.O]

As it stands, and the pics show (though tough to see I'm sure) I've cut away quite a bit of the box. If I cut some more, then I could use solid insulated pipe all the way down. My concern was cutting too much away, but I think Mike O. addressed this when he said:
" Then install a block off plate after and seal any open spaces with fireproof insulation." However, I don't know what you mean Mike?

If you mean a plate that would be flush with the face of the stone wall, I don't intend to do that because the wood stove is tucked in behind the plane of the brick wall by about 4 inches, and doing so would mean lost heat from the stove that could have been inside the house.

Also, I need to be able to get in there and remove the piece on the bottom of the "T" in order to clean the chimney. Can I simply fabricate steel plates that surround the pipe on the "ceiling" of the firebox once it is installed? With insulation around that? Does that make sense to you guys?

My stove is running, so I cant get any pics right now, but if you Google Image "Fireplace block off plate" you will get lots of results. Most people install the block off plate on the "Ceiling" of the fireplace, to on the face. Yes, just install some sort of cut-to-fit plates to fit nicely into the fireplace and around the pipe.

I'm sure someone can chime in with pictures of an install.

 

[bholler]

As it stands, and the pics show (though tough to see I'm sure) I've cut away quite a bit of the box. If I cut some more, then I could use solid insulated pipe all the way down. My concern was cutting too much away, but I think Mike O. addressed this when he said:
" Then install a block off plate after and seal any open spaces with fireproof insulation." However, I don't know what you mean Mike?

If you mean a plate that would be flush with the face of the stone wall, I don't intend to do that because the wood stove is tucked in behind the plane of the brick wall by about 4 inches, and doing so would mean lost heat from the stove that could have been inside the house.

Also, I need to be able to get in there and remove the piece on the bottom of the "T" in order to clean the chimney. Can I simply fabricate steel plates that surround the pipe on the "ceiling" of the firebox once it is installed? With insulation around that? Does that make sense to you guys?

Just use heavy flex and insulate it there is no real benifit to rigid liners.

 

[antlerman]

Okay, so it sounds like there is no real advantage to solid, so I'm thinking i'll go with flex, especially since it's easier to install.

Can I get insulated flex that does NOT need to be wrapped in insulation?

Also, I thought I saw on a post somewhere on here that Dura.... (something) was recommended highly. Is one brand really better than the other?

 

[bholler]

Okay, so it sounds like there is no real advantage to solid, so I'm thinking i'll go with flex, especially since it's easier to install.

Can I get insulated flex that does NOT need to be wrapped in insulation?

Also, I thought I saw on a post somewhere on here that Dura.... (something) was recommended highly. Is one brand really better than the other?

Dura liner is a nice preinsulated rigid system that has flex sections that can be added to the bottom to get through the damper area. Or there are preinsulated flex liners as well.