How do I know if I need a liner?

[Shaggyant]

It seems like half the threads in this forum are about installing stainless liners. Why is this and how do I know if I need one?

My house was built in 1987 and it has a rectangular chimney with what looks like a clay liner in it. The guy who inspected it when I bought the house said the chinned looked like it was hardly even used and looked great.

I have been burning every day in it and everything seems fine. Why would I need a liner And how would I know?

Thanks for the knowledge help.

 

[Batman]

An insulated liner will keep the flue gasses warmer, reducing condensation and creosote deposition. The draft will improve. Most of all, it will provide the peace of mind that comes from knowing that should there be a chimney fire, there is a stainless steel tube and a half inch of ceramic insulation between the fire and the rest of your house.
In a recent thread, someone posted a video of a simulated chimney fire in a terra cotta flue. Worth a look. That said, there are many (most) that don't have liners and live to tell about it.

 

[Shaggyant]

I get the benefits but most people don't dish out thousands of dollars unless there is something actually wrong with what they have now. I can't see putting in a liner just because it's what all the cool kids are doing.

What I do see is a ton of stories on the internet about chimney companies that push liners on everyone pretty much no matter the condition of their chimney.

What things could be a legitimate reason for for using a liner as a repair? What should I look for in my personal chimney that might be cause for installing a liner?

There is already four inches of terra cotta and cinder block between the chimney gasses and the wood in my house. When I go out into the garage while burning the exterior of the cinder block chimney is ambient temps when my thermometer says the flue gasses are 500*+.

An insulated liner will keep the flue gasses warmer, reducing condensation and creosote deposition. The draft will improve. Most of all, it will provide the peace of mind that comes from knowing that should there be a chimney fire, there is a stainless steel tube and a half inch of ceramic insulation between the fire and the rest of your house.
In a recent thread, someone posted a video of a simulated chimney fire in a terra cotta flue. Worth a look. That said, there are many (most) that don't have liners and live to tell about it.

 

[begreen]

Shaggyant, what is this chimney servicing - a fireplace, stove, insert? Does the chimney have 2" clearance from any and all combustibles including framing and drywall?

 

[Shaggyant]

Shaggyant, what is this chimney servicing - a fireplace, stove, insert? Does the chimney have 2" clearance from any and all combustibles including framing and drywall?

It's servicing an old '92 model Quadrafire 3100.

I'm not sure how you would determine that? The chimney is original from when the house was built and it butts up to the backside of my living room inside the garage. It's pretty much a cinder block tower on one side of my garage that pokes out through the roof. The cider blocks touch the garage wall all the way up to the ceiling and then it pokes through the garage ceiling and The roof above it at just about the top of the ridge line of the house.

The living room has a nice hearth area made of natural stone and the single wall stove pipe comes up out of the top of the stove about two feet and then goes back to the wall whith the chimney on the other side where it enters through a big sheet metal thimble about a foot and a half in diameter that covers the surrounding Sheetrock of the living room.

I'm sure it is built to whatever 1987 code was at the time.

 

[begreen]

You would hope so, but unfortunately code adherence is not guaranteed, especially if the inspection was lax.

The purpose of a liner is to increase safety and enhance stove performance. They are not required for all installations, but desirable in many.

 

[kennyp2339]

Piece of mind for most, masonry chimney's may meet the right codes of having 2" to combustibles, but during a chimney fire when temps go over 1500deg your depending on mortar joints holding and clay tiles not cracking.
What's puzzling with masonry chimney's is the #1 killer, moisture, yet at least around my area (NNJ) only half the chimney's I see have some type of cap to keep the weather out.
Personally if I had a masonry chimney, I wouldn't want to take the chance of depending on just a clay liner, especially if the house has been built for a while, and its been exposed to the weather, that's me though. Plus an insulated liner like other posters mentioned would keep flue gases warmer, reducing the formation of big bad creosote.

 

[Shaggyant]

Piece of mind for most, masonry chimney's may meet the right codes of having 2" to combustibles, but during a chimney fire when temps go over 1500deg your depending on mortar joints holding and clay tiles not cracking.
What's puzzling with masonry chimney's is the #1 killer, moisture, yet at least around my area (NNJ) only half the chimney's I see have some type of cap to keep the weather out.
Personally if I had a masonry chimney, I wouldn't want to take the chance of depending on just a clay liner, especially if the house has been built for a while, and its been exposed to the weather, that's me though. Plus an insulated liner like other posters mentioned would keep flue gases warmer, reducing the formation of big bad creosote.

So, basically what you are saying is that it's unsafe no matter what the condition and you shouldn't be operating a wood burning stove without an insulated stainless steel liner or a class a stainless steel chimney in place?

 

[kennyp2339]

No, masonry liners a perfectly safe if there built to today's required clearances, maintained annually, and the user understands them.
It's kind of like new technology, there's nothing wrong with the older stuff if properly working, but there's a reason why there's newer. Just my opinion though

 

[Shaggyant]

No, masonry liners a perfectly safe if there built to today's required clearances, maintained annually, and the user understands them.
It's kind of like new technology, there's nothing wrong with the older stuff if properly working, but there's a reason why there's newer. Just my opinion though

Ok, how does someone tell if the masonry chimney needs to be repaired or replaced? This is what I'm getting at.

How do I know if it's properly maintained and working aside from burning my house down? There has got to be some sort of way to look at it or test it to see if it is still safe to operate.

It's like this. New cars get better mileage and better emissions and better crash protection but I can't see buying a new car every year just because of that. I want to know how to tell when my old car has bit the dust and actually needs replacement.

 

[kennyp2339]

A good chimney company, a higher tech company will scope the chimney with a camera, they will look at the crown, look for signs of water intrusion, sinking footing, operation and seal of the clean out door.. ect
Some use a flashlight and mirror, IDK about trusting that though

 

[srchar]

I opted for a stainless liner because my clay tiles were to big. I have an external brick chimney with 7"x11" ID terra cotta tiles. Everything I read said that it was too big to draft well with a 6" EPA stove especially because it's an external chimney. If the tiles had been an appropriate size I would have had it inspected and used it as is.

What size are your tiles?

My $0.02

 

[bholler]

Ok, how does someone tell if the masonry chimney needs to be repaired or replaced? This is what I'm getting at.

have it scanned by a reputable chimney company. Watch the camera as they scan and ask them to point out any flaws. there can be cracked flue tiles or bad mortar joints either of those are reason enough to line the chimney. The lack of clearance to combustibles is also a good reason to install an insulated liner. i am a sweep and i install lots of liners but i also clean allot of clay lined chimneys that work just fine as well. Clay is not bad but insulated stainless is better. And yes there are scammers out there that will go around telling every customer they need a liner that is why you should choose a reputable pro

 

[Shaggyant]

have it scanned by a reputable chimney company. Watch the camera as they scan and ask them to point out any flaws. there can be cracked flue tiles or bad mortar joints either of those are reason enough to line the chimney. The lack of clearance to combustibles is also a good reason to install an insulated liner. i am a sweep and i install lots of liners but i also clean allot of clay lined chimneys that work just fine as well. Clay is not bad but insulated stainless is better. And yes there are scammers out there that will go around telling every customer they need a liner that is why you should choose a reputable pro

Awesome!
This is exactly the info I was looking for. I will call around and see if any chimney sweeps in my area have a camera probe to check my lining. How much should something like this cost?

I'm not opposed to relining or even total replacement of the chimney but I'm just not the type of person who replaces things without a reason. It's good to hear that it is possible that my clay lined chimney may not in fact be so evil that it needs immediate replacement just because.

 

[Smoked]

If you are a DIY type, they are really easy to clean too. You will see all kinds of posts here where people burn all year and only get a coffee can of mainly ash/dust from their brushing.

 

[Snotrocket]

You see a lot of liner threads because that is what is used to either reline old broken down chimneys, or people using them to reduce the size of a fireplace flu.

You don't need a liner. Your clay lined chimney is perfectly safe and will work just fine. Keep it clean just like you would a stainless one.

 

[bholler]

You don't need a liner. Your clay lined chimney is perfectly safe and will work just fine. Keep it clean just like you would a stainless one.

Well i think that may be jumping the gun a bit the clay is over sized does not have proper clearances and has not been scanned. It may be fine but with the info given so far there is very little to say that.

 

[nellraq]

Well i think that may be jumping the gun a bit the clay is over sized does not have proper clearances and has not been scanned. It may be fine but with the info given so far there is very little to say that.

Sounds like your chimney would be classed as an interior chimney...ie not going up an outside wall but going up through the interior of the house. This is what I have....found a couple of small cracks in it..also it was too big (6" x 10" ID). I needed a 6" pipe for my new stove.
I removed the clay liner and installed a 6" stainless NON insulated liner. The stove works great. I cleaned it last week and got a couple of cups of black soot for my efforts!! No sign of glazed creasote at all.
The ss liner was easy to install and MUCH cheaper than an insulated one.
Works for me,

 

[bholler]

The ss liner was easy to install and MUCH cheaper than an insulated one.

yes but there is still a danger of heat transferring through to those combustibles and catching them on fire. If you removed the tiles why didnt you insulate? Cheaper is not always better

 

[RyanStorm]

I wanted to ask to everyone, is the new stainless steel insulated liners, are they mandatory now if you put in a new stove, or are you allowed to use old piping, like mine, which is like a thick galvanized steel?

I read for zinc exposure that steel needs to be heated to 1100 degrees, but my stove only uses that steel on from the tee piece and up. They use only the same black steel as my stove on the inside.

 

[bholler]

I wanted to ask to everyone, is the new stainless steel insulated liners, are they mandatory now if you put in a new stove, or are you allowed to use old piping, like mine, which is like a thick galvanized steel?

Are you talking about a class a chimney system of a masonry chimney? Where is the galvanized pipe?

 

[RyanStorm]

Are you talking about a class a chimney system of a masonry chimney? Where is the galvanized pipe?

This is outside, the part I want to know if people generally are mandatory to change out:


This is inside, if that Tee piece at bottom of galvanized steel comes inside at all, its covered by that piece of metal.


I plan to get a quote this week, and maybe a city inspector, so I can see full cost for a brand stove from his store and his new professional install, or buying a stove from home depot and installing it myself with my current pipe, or buying a new kit if a must have.

 

[nellraq]

yes but there is still a danger of heat transferring through to those combustibles and catching them on fire. If you removed the tiles why didnt you insulate? Cheaper is not always better

In my case, insulating the liner was not necessary. The only part of the chimney exposed to outside temps is the last 3 feet, and i insulated that area with roxul.
I don't mind spending $ when necessary...but i dislike wasting $.
BTW, the guy who inspected the installation had zero problems with the chimney and passed the entire install with no problems at all.

 

[bholler]

In my case, insulating the liner was not necessary. The only part of the chimney exposed to outside temps is the last 3 feet, and i insulated that area with roxul.

Do you have the required 2" of clearance from the outside of the masonry to any combustible material? If not then yes insulation is required. The requirement is about safety not performance. I don't know about code in Canada so i cant say for sure but in the us in your case it would be required. And i am pretty sure that it is required in canada as well

This is outside, the part I want to know if people generally are mandatory to change out:

WHat you have is totally different than what the poster is referring to you have a class a chimney i am sure the inside is stainless

 

[RyanStorm]

Do you have the required 2" of clearance from the outside of the masonry to any combustible material? If not then yes insulation is required. The requirement is about safety not performance. I don't know about code in Canada so i cant say for sure but in the us in your case it would be required. And i am pretty sure that it is required in canada as well


WHat you have is totally different than what the poster is referring to you have a class a chimney i am sure the inside is stainless

Oh he didn't have pictures so I thought we might be talking about same thing...at least I didn't need to make a new thread