Question about re-lining chimney

[begreen]

If exterior, then I would strongly consider an insulated liner. Are you sure this is an 8x8 chimney? 8x8 sounds rather small for a fireplace. If so, is that ID or OD?

 

[hydes2004]

8x8 inside diameter but im going to double check tomorrow.

 

[begreen]

I suspect that liner should be insulated.

 

[chimneylinerjames]

It does need to be insulated. Are there terra cotta flues in the chimney? If so they an be removed by a professional and that would give you more room to work with. But if not, you could use the 7.5" and the pour down insulation. You don't have too many options here with that size of chimney. Just another thing to keep in mind, those measurements you see for liners, 7.5", 8", that is inside measurement. The OD would be 1/4" larger, so the 8" is actually 8 1/4" OD, so keep that in mind when ordering.

 

[hydes2004]

I believe it is a Terra cotta flue. My grandfather built this chimney about 40 years ago. What do you mean pouring insulation down there? I thought it was some sort of wrap???

 

[chimneylinerjames]

What do you mean pouring insulation down there?

There are 2 types of insulation, a wrap and a pour down. The wrap as you know is like a blanket around the liner then it is installed. The pour down is a mix that is poured around the liner after it is installed. You install the liner with nothing on it, just the liner. Block up and spots where it may leak out, so if this is for an insert, reach up into the smoke chamber and block the corners with some insulation to stop the pour down insulation from leaking out.

Or I have used a flat top plate on the bottom of the liner. Install the liner into the fireplace, install a flat top plate in the fireplace and pull up on the liner. Secure the top plate to underside of the flue and pour down the insulation. Make sense? You know how a normal flat top plate looks on the top of the chimney, now imagine another one on the bottom side of the flue attached to the liner, it is there just to stop the insulation from leaking out.

This insulation is a dry mix, you mix it with just a little water, not much just to keep it damp. You pour it down and it hardens a little. Not like concrete just stiffens up. If you don't like that idea of a hard mix, you can pour down the first bit damp then the rest in dry. Just in case you ever have to remove the liner it would be easier this way, still not easy but easier. It would be a mess to remove but doable.

http://chimneyresource.com/chimney-liners/chimney-relining/fireplace-chimney-liner/
That page shows a fireplace liner install but it would be the same idea with blocking up the corners. Obviously you wouldn't have to smooth out the smoke chamber walls as shown, but you get the idea of blocking up the corners so the insulation doesn't fall down. You would just have the liner continue down to the stove.

 

[hydes2004]

Any idea on what the less expensive option is?

 

[chimneylinerjames]

Well it all depends on how much you need. Generally in my experience they are close in price. But if you can fit the wrap insulation in the chimney, I would use that. Look at some sites, they have calculators that tell you how much you need.

http://www.chimneylinerdepot.com/store/4607/product/Insulation-Mix-40lbs..html

Here is a calculator that tells you how much you need. But many sites sell different size bags/boxes of insulation so make sure you use each websites calculation, it may be different amounts for different sites.

 

[clemsonfor]

I found a 7.5" round liner from chimneylinerdepot.com. I'm going to double check my measurements when I get out of work tomorrow and go from there

7.5" will be close to 8"s outside will that still work in your chimney? If that wont work i think a 7" will be fine.

 

[clemsonfor]

someone on here said that they used Roxul and cut the batts in half i beleive and used them to wrap thier liner length wise with it. I think this was for 6" flex but still i think they used less than $50 to insulate it.

 

[hydes2004]

Hmm, never heard of roxul insulation. I'd imagine its fire retardant right?

 

[webby3650]

It's very odd to have an 8x8 flue for an open fireplace. Is it a very old unlined chimney? I've seen a few 8x12 flues on fireplaces, that didn't draw well, but not an 8x8.

 

[pen]

If it is 8x8, and you fit a 7.5 in liner down it, I'll be impressed. It was all I could do getting a 6 inch liner down a 7.25x7.25 chimney w/out damage, and that is with chimney tiles that were pretty darn straight.

As others said, specifics on this chimney are necessary for more options.

pen

 

[hydes2004]

Got home a little late today. Its dark out however I might just go up there.

 

[pen]

Got home a little late today. Its dark out however I might just go up there.

Take a flashlight, and let us know if you fall off. Remember pics or it didn't happen.

Stay safe.

pen

 

[clemsonfor]

im betting this is a block or brick unlined chimney.

Roxul is fire retardant insulation. WEll fiberglass is not flammable but also not rated to be up next to like a chimney or flue. But this stuff is labled to be next to a brick or steel chimney. Google it. They use it on acoustics as well for sound dampening. ITs like some sort of rock or something that is basically busted up or something into like fibers that are bound into the insulation, so it cant melt or turn hard like fiberglass because its basically a rock.

 

[clemsonfor]

you would use pour insulation for example if you only have like a 1/4 inch clearance or so because you can pull the wrap blanket down the chimney with those tight clearences.

 

[hydes2004]

Im waiting for the fiance to get home from work, then I'm going to go up there and take another measurement in the meantime since you guys have been so helpful, do you known what the best temp to burn the winterwarm is? The manual really didn't specify. I have bought a condor inferno stovetop thermometer for it. Going to put it on the top left of the door, it should be in next week. I also purchased a mostiure meter from Lowes. Not sure how accurate it is or where the best place to measure wood is. I. Checked a few splits that I store in my basement breezeway and they read 17-19 %. Im lucky enough to get seasoned wood from my dad's buddy for $150 a cord . Thanks for all the help guys. I'm 26 and having really had any experience with a wood stove.

 

[webby3650]

Checked a few splits that I store in my basement breezeway and they read 17-19 %

Did you split the piece of wood first? It must be split to get an accurate reading. Put the probes in line with grain in the wood.

 

[hydes2004]

Wood came pre-split. Should I split again and check it??

 

[webby3650]

Wood came pre-split. Should I split again and check it??

Yes, check it in the middle. I bet it's 27% on the inside.

 

[hydes2004]

Standby going to do that right now.....

 

[hydes2004]

I know under 20% mostiure is ideal but what's the "high limit". I have more wood outside, some of it was snow covered and we are having a thaw this week.

 

[webby3650]

Just use 20% as an average. The lower the better.

 

[hydes2004]

I'm an idiot, just got off the roof. Inside diameter if the Terra cotta is 10x10. I only need 15' of stainless liner

So where do we stand. I should be able to get the liner and insulation down there right????