What's new

Chimney liners


kinder and gentler
May 20, 2020
Member Number
lake erie
how do they work?
My mother in laws liner has apparently sagged in the chimney and now the wall thimble is all fucky and it doesn't seal for shit.

My plan was to clean it, send a camera down it to make sure that it's not separated inside and then hoist the bastard up 8" at the top and secure it again.
I have never done any of this before and the roof is clay tile that terrifies me.

I'm going to see if I can get a towable boom lift near enough, but fucking trees and powerlines everywhere.

The chimney people refused to go onto the roof to stick a camera down it and see if it was fucked or not, so they just quoted the "you need a new one" price of 10 grand. The chimney itself is in OK shape and was repaired when the roof guy fixed all the flashing up there 2 years ago.
I'm not ruling out that guy didn't get it put back together properly, but it's a little late now.

so how fucked am I? It's probably 40 feet of liner, from the basement wood stove to a tall peaked 2nd story roof. about how much is it gonna weigh and how fucking stuck is it going to be?
​​The answers gunna be pages long.
Knee jerk reaction, it is not installed RIGHT.
It needs to be secured (depending on code) in multiple points in the chaseway.
Suspended by the top only, allows the joints to pull apart (if not screwed together) held up by the ceiling thimble takes one hella mounting!

Oh and in before the"you're gunna burn the house down crowd":flipoff2:
Last edited:
it's not a solid liner.
it's a stainless flex pipe with a horizontal 90 to a free standing wood stove in the basement. It was installed after a chimney fire like 10 years ago. They used the grout style insulation. Everything was cool until last year.

The instructions say that you're just supposed to tighten a hose clamp in the top plate to secure it and that the top plate bears all the weight.

I'm about 90% sure it's this:
Location in country
Single wall?
dia. Of pipe?
Straight shot up?
What termination top\bottom?
You need a REAL Chimney Sweep!
So brick chaseway?
if the top clamp did not slip, you got issue's...
like torn flexpipe.
If the grout is all that is sealing the flame path to the outside you need to stop using it.

If the tin flex just sagged (read got longer) and is solid you may be able to just trim it off. Maybe!

Camera sounds like a GOOD IDEA!
Try a home inspection dork if you cannot find an honest sweep!
Location in country
Single wall?
dia. Of pipe?
Straight shot up?
What termination top\bottom?
You need a REAL Chimney Sweep!

northern ohio
centrally located in the house, follows the sair well up.
Maybe 6"?
Pretty much a straight shot to the cap yes. Multiple pipes in the same masonry. Another liner to a fireplace directly above, separate flue. and the combined furnace/water heater flue in between them at the roof.
Bottom termination is one of these:

I haven't been on the roof yet, but it's some sort of plate with a rain cap on the top and I'm assuming it's from the same system and is one of these:


my hope is that the liner itself isn't fucked and that I can just fix whatever is not right and put it back where it belongs.
I demolished the fireplace and outside chimney on my other house . The 30 foot liner was saved and two of us rolled it into a coil..it was encased with something like sand. I sold the liner which fit into a pu truck
. I bought a woodstove, installed a stainless multi wall chimney up through a chase I built and through the roof...
here's what we're working on.

stairwell continues to the 2nd story. That's an exterior door there. It's pretty much center of the house.
Second photo is the cleanout in the basement, full of the deteriorating insulation because shit is moving or something in there.
third photo is the cap, the one on the left is the wood stove. one on the right is the fireplace up stairs. middle is the furnace/water heater.
sorry for the max zoom, but it's fucking up there.



The bottom tee is a cleanout\soot basin.
if they poured theramix insulation down the comm chase, it gunna complicate repair.
Once you know there are no leaks repair as needed.
IF you can unhook both ends and snake it out to verify integrity and re install I would rock that idea.

Theramix insulation looks like grey perilite and portland c ment
Here's the inside of the T connector or whatever it's called.
It's moved down and rotated about 45 degrees to the right.

Is the grey media inside the vent pipe or just in the bottom of the chaseway?
If inside the pipe integrity is gone!
if I'm going to commit to pulling it out to have a look at it then I'll just buy a new setup and install new shit.
If I can get a camera down it from the top and make sure it doesn't suck is that going to be good enough? I've got a 25 foot jobby. I'll just have to figure it out.

If I can't see any splits, can I just pull it up, secure it and then fix the insulation?

Obviously the next step is getting on the roof and having a look at that, but it's not gonna be today.
Is the grey media inside the vent pipe or just in the bottom of the chaseway?
If inside the pipe integrity is gone!

I haven't seen anything but ash and creosote in the actual liner. It's just at the bottom in the old cleanout.
Edit for post 12
yes .

post 13
Thats positive.
looks like the liner shifted insid the chase.
if it was loose and had a kink (for lack of a better word) and it straightened out yer golden...
where is the lid penetration issue?
you said like 8" hanging down or something...

25' vidieo lead right?
rent a set of fiberglass chimney sweeping rods, and fix camera onto it and run up from the bottom, then the top.
that shound get ya eyes on it all.
rotate camera on each section as you go
Last edited:
Just reading the data sheet, looks like this has most likely installed loose.
the only thing I see is "no more than 50' should be supported by a union of 2 sections of flex.(here is a possible failure point of the coupling)

Lookin at the creosote buildup ya need to sweep this beast before reuse.
The tee having twisted leads me to think there was a twist in the flex that has worked loose, and dropped down and turned the tee...
Look up chimney fire (creosote) things are a beaoch.

If the union is solid pull it up top and trim off after you have yer bud square up the tee end to appliance.
There will be some form of clamping device on the top termination plate to secure the flexpipe and cap.

we have the fiberglass cleaning poles.

I'm going to clean and inspect. there is apparently one coupler in there, so that's the most likely suspect if the top isn't connected to the bottom anymore
Here's the inside of the T connector or whatever it's called.
It's moved down and rotated about 45 degrees to the right.

what the fuck no wonder they had a chimney fire they gotta run that thing hotter
no input here, I've just got a terra cotta liner in those square cinder blocks, it stays clean because I run it real goddamn hot
  • Like
Reactions: Clb
Not fukt yet...
is the flue sized at 1\12th firebox opening as per the detail page thing you posted?
Defiantly needs more airflow\heat in the box.
that was the chimney sweeps "we'll fix it" attempt at just jamming the pipe in there and filling the whole fucking thing with fireseal. So it's probably 70% of the diameter it's supposed to be at the thimble. It's also bent the shit out of it, so if the liner isn't wrecked If I can pull it up we may just have to buy a new wall thimble piece to hook onto the liner.

as always, finding a competent company is proving fucking impossible, so here I am to just do it myself.
There are some decent supply companies online if you can verify what you need, Copperfield for one.
Replace the fubar, fix the wall up nice and wait for the cold happy it's DONE .
Good luck, I will keep an eye on this.
Top Back Refresh