Chimeny Experts, advice needed on existing clay liner

[barnaclebob]

I just had a chimney company out to see if it is possible to create a new hook up for a stove requiring a 6" flue to my existing chimney. He seemed to indicate that a liner was definitely needed even though he also said the clay liner went all the way down the chimney.

He also said he wouldn't be able to fit a 6" liner because the existing flue was just at 6" but there were some lips that would catch the liner down further so he only gave me a quote for installing a 5" liner which wont work for a progress hybrid. ($1700 for a 25' 5" chimney SS liner, cap, and thimble.)

Assuming the clay liner is in good shape, is a stainless liner needed? If its not in good shape then what are the options from there? Any recommendations for a chimney company in the North end of Seattle?

I just did some googleing and apparently square liners exist. A 5" square liner would give me about the same cross section as a 6" circle, is that a good option?

Thanks for reading.

 

[double-d]

Clay Tile Flue Liners are rarely in "good shape", it doesn't take much to find a crack tile or gap in the mortar joints. A camera inspection would be needed.
Depending if you are coming out of the wall through a thimble or fireplace opening. they also make a 5.5" Flex liner (5.75" OD), this would only work if you are going through the fireplace open, going through a wall thimble, you will use a 5.5" tee, and that is the same size as a 6". You would need to check with the stove mfg if the 5.5" liner was approved.

Insulation is always recommended and usually required. Sounds like having the clay tiles removed would give you around 8" x 8", now you have room for a 6" liner with insulation.

 

[bholler]

Well you dont want a 5" liner. There are almost no stoves approved to run on that. Because of that i would automatically rule out that guy. He may be right it may need a liner but he is trying to sell you the wrong thing. If it needs a liner the tiles should be removed and an insulated 6" liner should be installed

 

[barnaclebob]

Thanks for the replies. The chimney guy did say that removing the clay is an option but would be cost prohibitive and could involve tearing down and rebuilding much of the chimney from the attic up. It is a two story house + attic. This is a new hookup where they will have to go through the wall and make a new hole in the chimney. Does that sound right?

When is an insulated liner required instead of just recommended over an uninsulated liner? I'll be calling a few other places today as well to see what they think but I'm guessing a square liner will give me the most cross section without having to tear down a chimney.

 

[Mrpelletburner]

Insulation is always recommended and usually required. Sounds like having the clay tiles removed would give you around 8" x 8", now you have room for a 6" liner with insulation.

Just wanted to chime as I am in a similar boat.

Also recently had my chimney cleaned/inspected. They suggested an insulated liner 6" 25', as it provides a extra fire barrier. Was quoted $1700 to install the liner, $600 for labor. An additional $300 to break out the existing 8x13 clay liner (which is not in bad shape, they ran the camera through it) and $200 to remove the adjacent pellet stove 4" liner so they can break out the clay liner and not wreck the pellet stove liner. So about $2,800 to install a liner. Needless to say, I did not hire them. However, if they had quoted $1,700.... would of hired them to take on the job.

Local stove shop sells the kit for ~$900 6" 35' kit, will "attempt" the install myself, minus the insulation.

 

[Mrpelletburner]

When is an insulated liner required instead of just recommended over an uninsulated liner? I'll be calling a few other places today as well to see what they think but I'm guessing a square liner will give me the most cross section without having to tear down a chimney.

I have the same question and found this thread. http://www.greenbuildingadvisor.com...tainless-steel-chimney-flue-really-need-insul

Local building inspector stated if installed within an existing clay liner and has the correct distance from the nearest combustible wall, you do not need to insulated the liner. Again, that is just for where I live.

 

[barnaclebob]

I have the same question and found this thread. http://www.greenbuildingadvisor.com...tainless-steel-chimney-flue-really-need-insul

Local building inspector stated if installed within an existing clay liner and has the correct distance from the nearest combustible wall, you do not need to insulated the liner. Again, that is just for where I live.

My county website (snohomish wa) says they use the 2015 international residiential codes which says "solid masonry units or hollow masonry units with not less than 4 inch nominal thickness" under the "Chimney walls with flue lining" section. The chimney guy did say I have the 4" of thickness so it does sound like I don't need insulation at the very least.

https://codes.iccsafe.org/public/document/IRC2015/chapter-10-chimneys-and-fireplaces

 

[double-d]

"Green Building Advisory" - "A rep for one of the large internet retailers has stated that the AES wrap is actually used to provide a firebreak zone between steel liner and masonry and does not really act to keep the vapor warmer in any meaningful way."

When stove is lit in a lined and insulated chimney, the cold air will only be trapped inside the liner (typically 6″ in diameter). The heat from the gasses heat the metal as they rise, warming the flue and making it easier to heat the cold dense air. The insulation prevents heat loss from the metal liner, keeping more heat in the chimney. The hot gasses get to the top faster, (hot air rises) getting your stove up to temperature quicker. This also minimizes the chance of smoke coming back into the room. Warmer the gases, less creosote buildup.

 

[yooper08]

My county website (snohomish wa) says they use the 2015 international residiential codes which says "solid masonry units or hollow masonry units with not less than 4 inch nominal thickness" under the "Chimney walls with flue lining" section. The chimney guy did say I have the 4" of thickness so it does sound like I don't need insulation at the very least.

https://codes.iccsafe.org/public/document/IRC2015/chapter-10-chimneys-and-fireplaces

I believe that's just chimney construction. You need a liner and at least 4" of masonry around that. What you'll also find is that there is then clearance to combustibles to the masonry. And if I'm not mistaken, UL testing, which is done with insulation, is performed with 4" of masonry.

Net net is insulate the liner. It's the way to go from both a safety and performance perspective.

 

[barnaclebob]

I think the chimney was 16" square top to bottom so with a 6" flue that would leave 5" on each side including the liner so I'm still good for that code. Most of the chimney is buried behind walls so I can't check if it meets the clearance to combustibles in the wall. Insulation isn't happening unless another chimney company says they can tear out the clay liner for under a grand or so. I just need to make sure I meet the codes vs exceeding them.

Thanks again for all the replies.

 

[bholler]

My county website (snohomish wa) says they use the 2015 international residiential codes which says "solid masonry units or hollow masonry units with not less than 4 inch nominal thickness" under the "Chimney walls with flue lining" section. The chimney guy did say I have the 4" of thickness so it does sound like I don't need insulation at the very least.

https://codes.iccsafe.org/public/document/IRC2015/chapter-10-chimneys-and-fireplaces

You are missing the part about the required clearance to combustibles from the outside of the masonry to any combustibles. Which if this is internal needs to be 2".

Breaking out the old clay should not cost $1000 unless there are some extreme complicating factors. And if you cant verify those clearances you need insulation. Also in almost all cases if you want to comply with the ul listing which is also a code requirement you need insulation.

 

[barnaclebob]

That's good to know. What is the typical process to remove the clay liner? Some quick googling shows that its some device put on the end of a drill that flails around and breaks up the clay which doesn't seem that hard. Can those work 25' down?

The chimney sweep said it would require rebuilding the chimney or some other very difficult method.

 

[bholler]

That's good to know. What is the typical process to remove the clay liner? Some quick googling shows that its some device put on the end of a drill that flails around and breaks up the clay which doesn't seem that hard. Can those work 25' down?

The chimney sweep said it would require rebuilding the chimney or some other very difficult method.

Yes they easily work at 25'. And you really need to get someone else out there

 

[barnaclebob]

Ok I had another company out. It was harder to find companies that install liners for wood stoves than expected and another company canceled on my the day before because "their estimator was no longer with the company". I guess most people are converting to gas these days.

These guys really seemed to know what they were talking about and thought that the clay liner would most likely need to be broken out which could be difficult due to the small size of the chimney itself. He was going to have his mason come out in a few weeks and run a camera down it to make sure but said removing the clay and doing any possible repairs to the bricks could be in the $1800-2500 range then another $1200 for the insulated liner. Even if that's on the high side I'll probably go with them because they seem very experienced, are booked out a few weeks at least, and I need it done. Buy once, cry once.

 

[begreen]

If you need more quotes try:

Chimcare Portland
712 Warren Ave N
Seattle, WA 98109
(206) 539-1450

Adrian Runaas
7626 #B 8th Ave. SW
Seattle, WA 98106

(206) 475-0982

 

[barnaclebob]

More updates to my ongoing chimney situation.

After some more measuring the chimney company I have been talking to said the best option is to take out the whole chimney because the current flue is too small and there is no gap between the clay liner and the brick. I assume that makes it difficult to break out the liner?

However that may all be moot because I was up in the attic building some storage platforms and found a cavity right next to the chimney that's about 16"x16" square and it goes from the attic, through the second floor, to the first floor ceiling to right above where I want the stove to go. This cavity was hidden under insulation. I should be able to run the new chimney right up into the attic and out the roof with minimal added cost. Now I just need to get them on the phone again...

The picture is from the attic looking down.

 

[begreen]

When putting in the chimney pipe they should add a fireblocking attic insulation shield.

 

[barnaclebob]

When putting in the chimney pipe they should add a fireblocking attic insulation shield.

Thanks, I'll make sure that's included in the quote.

 

[peakbagger]

I have helped take old chimneys out in the past, its not rocket science, just a lot of grunt work. As long as you have window on each floor just set a tarp on the ground and tarp off the room, then get an electric jackhammer and go at it throwing the bricks out the window onto he tarp. If the bricks come out whole, you can usually list them on craigslist and folks will haul them away for free. Years ago my friend was tight on bucks when he bought a house and we topped out the blocks above the roof line with used bricks he had scrounged from somewhere else. No good reason to leave a useless chimney in place.

 

[begreen]

I pulled out a 2 story furnace chimney and full fireplace before we raised the house. Each took about 3 days. The old 1924 fireplace had a lot of brick but it came out pretty easily. I tented a corridor heading to a side window. The furnace chimney was a lot newer and more work. I did this with hand chisels and hammer with the help of my son.

 

[barnaclebob]

The chimney guys confirmed that they can run class A in the cavity I found but they want the stove in place first so now its time to build a hearth and set a date for the stove delivery.