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Discussion Starter #1
Just moved into an old home (200 years old)....
The original chimney is in pretty rough shape, but in good condition on the exterior - - I have three separate estimates from repair companies, and was looking for some input about the approach that we are leaning towards.
Option 1 - Mortar Liner: The company inserts a bladder into the chimeny and pours mortar into the opening. After curing, the bladder is removed, and a perfect mortar cylinder is left in the chimney.
Option 2 - Steel Liner: The company wants to just insert a steel liner into the existing structure (lowest cost option).
Option 3 - Combination: Drop a steel liner into the opening, and then backfill mortar along the sides. Mortar will cure, and the liner remains.

For me - Option 1 is extremely expensive (over $4,000). Option 3 was less than $2,000, and seems to give the benefits of both approaches.

Anything I need to take into account? Leaning towards the 3rd option, but would appreciate any input.

Thanks a ton for any input - I can't get this wrong, given the cost of the work!.!
 

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Is this a fireplace chimney or a boiler chimney?
Ron
 

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Option 1 has been used here for over 30 years now and there have been no real problems with the system. Perlite concrete is used which insulates as well as helping stabilise old flues. Main problem is the expense, but they will outlast stainless steel liners.
When s/s liners are used vermiculite/cement is normally put around the liner for insulation.
 

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Discussion Starter #4
Ron - This is a furnace chimney, so not connected to a fireplace...

Stuart - So, the mortar liner is the new standard for this process. Cost seems to be about 3 times what the stainless liner (backfilled with mortar). Given that this is for the furnace (and not connected to a fireplace), you think that the additional cost is warranted?

The trigger for having this work done is that we are getting moisture in the walls which is decaying the plaster walls along the chimney. The suggestion from our inspector was to get a steel liner to reduce moisture in the chimney. Wondering if the mortar liner is overkill in this situation.

Thanks for your input - Just want to validate my approach before I (literally!) send $4,500 up the chimney!
 

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For function, all you need is the stainless steel liner.
I converted from oil to gas and had to line the chimney with a 6" liner so the fired clay liner wouldn't disentegrate. It cost me $350.00 for all the parts. I could of had it done professionally for $1800.
You will have to open the side of the chimney to get the flexible duct around the jog in the flue pipe.
It isn't that flexible.
It's a little tricky wrangling 30 feet of pipe, on the top of your roof(slate), but once it's inserted into the flue, it's not so bad.
Ron
 

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Stuart - So, the mortar liner is the new standard for this process. Cost seems to be about 3 times what the stainless liner (backfilled with mortar). Given that this is for the furnace (and not connected to a fireplace), you think that the additional cost is warranted?

!
I wouldn't say it's the new standard here, as s/s liners are still more commomly used as they are cheaper. As people these days seem to move house more often they will usually go for the cheaper option.
As it's a furnace the extra cost may not be justified. How long is the guarantee for an s/s?
You can sometimes find that damp coming through the chimney will bring Hygroscopic salts from the flue into the plaster. These will attract condensation even at an R/H of only 50% and will continue to cause damp patches. If this happens hack off the plaster and render the base coat with 3/1 sand cement and an added salt retarder.
 
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