Insulated Chimney Liner vs Poured Concrete + Vermiculite

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Pre-Insulated or Vermiculite+Concrete

  • Vermiculite+Concrete

    Votes: 0 0.0%

  • Total voters
    8

Dekkars

New Member
Feb 5, 2019
8
Northeast
Hi All,

We have a masonry chimney with tiles that needs to be relined, and have two different quotes to do so. One involves a pre-insulated stainless steel liner while the other company has quoted us a stainless steel liner with vermiculite and concrete poured around it.

Both are quoting us to bust out and dispose of the old liner tiles.

Which one of these options is better? Both are in the same ballpark as far as cost goes but I can't find any information on the best way to go about this.
 
It depends on the condition of your chimney we will use pour in if it is an old chimney that could use the stuctural help. And there is room for enough pour in.

And yes you can pull a liner out of pour in pretty easily.
 
It depends on the condition of your chimney we will use pour in if it is an old chimney that could use the stuctural help. And there is room for enough pour in.

And yes you can pull a liner out of pour in pretty easily.

Chimney is two decades old, give or take. No mention of structural issues. There are two other flues that come out of that chimney as well, an upstairs wood stove and the furnace.

It is sounding like in general the pre-insulated is the safest way to go, and from what I've read should also be cheaper than the pour in option? Is it odd that both quotes are pretty similar?
 
Chimney is two decades old, give or take. No mention of structural issues. There are two other flues that come out of that chimney as well, an upstairs wood stove and the furnace.

It is sounding like in general the pre-insulated is the safest way to go, and from what I've read should also be cheaper than the pour in option? Is it odd that both quotes are pretty similar?
No the cost shoulder similar
 
Maybe I made the wrong assumption here (still voting for pre-insulated or insulation wrap). Is the vermiculite option just pre-mixed insulation or is it an insulation mix and then concrete?

The quote is, verbatim:
"Chimney Liner:
35ft 6" smoothwall stainless steel liner T kit to vent basement wood stove

Installation:
Install the liner to code standards. Provide and pour a vermiculite/Portland cement insulation mix around the liner."

From what I understand thats just a pre-mixed insulation?
 
The quote is, verbatim:
"Chimney Liner:
35ft 6" smoothwall stainless steel liner T kit to vent basement wood stove

Installation:
Install the liner to code standards. Provide and pour a vermiculite/Portland cement insulation mix around the liner."

From what I understand thats just a pre-mixed insulation?
Find out what is meant by smoothwall liner. Allot of that is not very durable
 
The quote is, verbatim:
"Chimney Liner:
35ft 6" smoothwall stainless steel liner T kit to vent basement wood stove

Installation:
Install the liner to code standards. Provide and pour a vermiculite/Portland cement insulation mix around the liner."

From what I understand thats just a pre-mixed insulation?
It sounds like a local company around here I have to deal with._g

Your post makes it appear that they're using a "home-brewed" version of poured chimney insulation to cut their costs. They take vermiculite or perlite and mix it with portland cement as a binder and then use it in place of the UL listed insulation mix that is required for the liner. This practice will, in all cases I've looked into, void the warranty on the liner as well as it's UL listing and as such is not a code compliant installation. In the event of any future issues, the installer will be liable should it come to that. Well, if you have a good lawyer they will. Get the liner pre-insulated or wrapped with ceramic wool OR make sure they use the proper insulation as required by the liner manufacturer. And make sure they ONLY use it. One or two bags for you to see isn't enough.
 
It sounds like a local company around here I have to deal with._g

Your post makes it appear that they're using a "home-brewed" version of poured chimney insulation to cut their costs. They take vermiculite or perlite and mix it with portland cement as a binder and then use it in place of the UL listed insulation mix that is required for the liner. This practice will, in all cases I've looked into, void the warranty on the liner as well as it's UL listing and as such is not a code compliant installation. In the event of any future issues, the installer will be liable should it come to that. Well, if you have a good lawyer they will. Get the liner pre-insulated or wrapped with ceramic wool OR make sure they use the proper insulation as required by the liner manufacturer. And make sure they ONLY use it. One or two bags for you to see isn't enough.
They could also be referring to one of the ul listed insulation products. I would ask them to clarify that and what is meant by smoothwall
 
They could also be referring to one of the ul listed insulation products. I would ask them to clarify that and what is meant by smoothwall
This is true. I may be projecting my frustration from having to explain to people why their high dollar stainless steel liner has an issue that it wasn't supposed to. I usually will refer to the poured insulation by it's brand name to avoid confusion when quoting said jobs. This contractor could be going either way and asking them to clarify exactly what they're using is what I should have said.
 
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They could also be referring to one of the ul listed insulation products. I would ask them to clarify that and what is meant by smoothwall

"The inside of the liner is smooth instead of corrugated to increase draft and stays cleaner. It also allows us to downsize, its the better style liner all around. The steel is 316 to prevent corrosion."

They quoted me an additional $750 for the pre-insulated install.
 
"The inside of the liner is smooth instead of corrugated to increase draft and stays cleaner. It also allows us to downsize, its the better style liner all around. The steel is 316 to prevent corrosion."

They quoted me an additional $750 for the pre-insulated install.
Do not get that liner if it is the 2 ply stuff. It is not durable at all. If you want smoothwall get midweight or heavy wall. And an additional 750 for preinsulated is way to much. Pour in costs very similar to preinsulated. And feild wrapped as well for that matter.
 
Do not get that liner if it is the 2 ply stuff. It is not durable at all. If you want smoothwall get midweight or heavy wall. And an additional 750 for preinsulated is way to much. Pour in costs very similar to preinsulated. And feild wrapped as well for that matter.

It is, and I quote: "2ply midweight". Although I was wrong about install, it is $750 flat which is significantly less than the pour-in. Not sure if it is worth asking for him to upgrade it to a single wall heavyweight, as it seems like he quoted me for the exact 2ply you were warning me about.
 
It is, and I quote: "2ply midweight". Although I was wrong about install, it is $750 flat which is significantly less than the pour-in. Not sure if it is worth asking for him to upgrade it to a single wall heavyweight, as it seems like he quoted me for the exact 2ply you were warning me about.
To my knowledge there is no 2ply midweight liner. It is one or the other
 
To my knowledge there is no 2ply midweight liner. It is one or the other

What should I be looking for them to install in the pre-insulated realm? Something like this?

https://www.rockfordchimneysupply.com/pre-insulated-flexible-stainless-steel-chimney-liner-kit.php

I've been looking over a lot of posts and it doesn't seem like they sell pre-insulated heavyweight liners. What separates a mid-weight pre-insulated from a 2ply pre-insulated?

Thanks for helping me make sure I do this right.
 
What should I be looking for them to install in the pre-insulated realm? Something like this?

https://www.rockfordchimneysupply.com/pre-insulated-flexible-stainless-steel-chimney-liner-kit.php

I've been looking over a lot of posts and it doesn't seem like they sell pre-insulated heavyweight liners. What separates a mid-weight pre-insulated from a 2ply pre-insulated?

Thanks for helping me make sure I do this right.
That is pre insulated lightwall. It will be fine but heavier liner will last longer. And midweight and heavy are smooth inside.
No they dont make preinsulated heavy wall but it can just be wrapped
 
Do not get that liner if it is the 2 ply stuff. It is not durable at all. If you want smoothwall get midweight or heavy wall. And an additional 750 for preinsulated is way to much. Pour in costs very similar to preinsulated. And feild wrapped as well for that matter.
I've got smooth wall 6" from Z-Flex, and while the inside layer is quite flimsy, overall, it's a very sturdy flex pipe, to the point it makes it difficult to make a turn. I don't think it will burn through any time soon.

Given the choice, I'd pay more and get heavy wall one, just because it would have been so much easier to install, because of how easy it is to bend heavy wall one compared to flex line. Too bad they don't carry it.

Edit: crap, I missed it... https://www.z-flex.com/productcart/pc/Heavy-Wall-Flex-Liner-117p2395.htm
 
Last edited:
I've got smooth wall 6" from Z-Flex, and while the inside layer is quite flimsy, overall, it's a very sturdy flex pipe, to the point it makes it difficult to make a turn. I don't think it will burn through any time soon.

Given the choice, I'd pay more and get heavy wall one, just because it would have been so much easier to install, because of how easy it is to bend heavy wall one compared to flex line. Too bad they don't carry it.

Edit: crap, I missed it... https://www.z-flex.com/productcart/pc/Heavy-Wall-Flex-Liner-117p2395.htm
They are by far the least durable type of liner on the market that is suitable for use with wood
 
How does it fail? Ie, what should I look for/expect in the future?
That thin inner layer gets snagged when cleaning leading to a hot spot that makes it get worse