Flex Liner Brands Recommendations

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Aug 20, 2014
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Eden, NY
I'm looking to buy a new liner. Has anyone purchased a 316Ti flex liner through Rockford chimney supplies? If so, are the liners well made? Any other brand recommendations?

thanks!
 
Well to start you only need 304 for use with wood no need to go to 316 it costs more. And I would recommend heavy wall flex over light wall it is much more durable. But absolutly stay away from the 2 ply smooth wall stuff. And as always insulate that liner no matter what you choose.
 
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Well to start you only need 304 for use with wood no need to go to 316 it costs more. And I would recommend heavy wall flex over light wall it is much more durable. But absolutly stay away from the 2 ply smooth wall stuff. And as always insulate that liner no matter what you choose.
I didn't see the 304 listed on Rockford website but I'll keep looking. Is the heavy wall difficult to work with? Would I be able to ovalize it?
 
I didn't see the 304 listed on Rockford website but I'll keep looking. Is the heavy wall difficult to work with? Would I be able to ovalize it?
oh its you again. Many times light wall is not available in 304. I have no clue what rockford has to offer. And no heavy wall is not hard to work with at all other than the added weight. And yes it can be ovalized also. But you would need an ovalizer to do it.
 
oh its you again. Many times light wall is not available in 304. I have no clue what rockford has to offer. And no heavy wall is not hard to work with at all other than the added weight. And yes it can be ovalized also. But you would need an ovalizer to do it.
yup, it's me again. Thanks for the info!
 
I just installed a 316 kit from rockford in august. seems to be quality and was an easy install
 
We sell Forever Flex 316Ti liner kits from Olympia Chimney Supply, who also manufacturers heavy-gage 304L liner. We've installed both types, and durability hasn't been an issue: in fact, both liners carry a lifetime warranty. We prefer the 316Ti, because it is WAY easier to install, and the 316Ti alloy can better withstand exposure to chimney fire temperatures than 304L. You can read more on our website at http://www.chimneysweeponline.com/foreverflex.htm

PS: we strongly recommend against ovalizing your liner to pass through the damper opening: if you've ever been drinking a milkshake and pinched the straw even the slightest bit, you'll see how that affects flow rate. Take a hacksaw, sawzall, cutting torch or offset grinder and enlarge the damper opening to accommodate the unsquished (technical term) liner. Your draft will be better, and it will be far easier to get your brush through at sweeping time.
 
We sell Forever Flex 316Ti liner kits from Olympia Chimney Supply, who also manufacturers heavy-gage 304L liner. We've installed both types, and durability hasn't been an issue: in fact, both liners carry a lifetime warranty. We prefer the 316Ti, because it is WAY easier to install, and the 316Ti alloy can better withstand exposure to chimney fire temperatures than 304L. You can read more on our website at http://www.chimneysweeponline.com/foreverflex.htm

PS: we strongly recommend against ovalizing your liner to pass through the damper opening: if you've ever been drinking a milkshake and pinched the straw even the slightest bit, you'll see how that affects flow rate. Take a hacksaw, sawzall, cutting torch or offset grinder and enlarge the damper opening to accommodate the unsquished (technical term) liner. Your draft will be better, and it will be far easier to get your brush through at sweeping time.
Thanks for the input!
 
We prefer the 316Ti, because it is WAY easier to install, and the 316Ti alloy can better withstand exposure to chimney fire temperatures than 304L
I find the heavy wall or their hybrid much easier to install it is smoother and much more flexible with no memory to it. Yes it weighs more but it is not that bad. And 304 stands up to chimney fires just as well as 316 but light wall does not stand up as well as heavy wall. Yes light wall will work fine but heavy wall is much more durable.

PS: we strongly recommend against ovalizing your liner to pass through the damper opening: if you've ever been drinking a milkshake and pinched the straw even the slightest bit, you'll see how that affects flow rate. Take a hacksaw, sawzall, cutting torch or offset grinder and enlarge the damper opening to accommodate the unsquished (technical term) liner. Your draft will be better, and it will be far easier to get your brush through at sweeping time.
I agree totally
 
Chimney liner materials have evolved over the 37 years I've been in the business. In the old days, they were mostly
type 304, then 316, then 304L or 316L, and most recently, 316Ti. At each stage, they became more resistant to a
phenomenon known as sensitization.

Sensitization is the condition where, at high temperatures, chromium carbide precipitation reduces the amount of
chromium in solution in the stainless steel. Since chromium depletion significantly reduces the liner's corrosion
resistance, and wood creosote is highly corrosive, sensitization is a condition to be avoided.

Today, the first line of protection is to use an L grade (low carbon) stainless steel such as Types 304L or 316L,
because lower carbon means fewer carbides to deplete the chromium. However, at temperatures over 700 degrees F
(easily attainable during a chimney fire) sensitization still occurs in the L grades.

A higher level of defense can be achieved using chemically stabilized grades of stainless steel, such as 316Ti. For these stainless
steels, Ti (Titanium) is added to the alloy. Titanium combines with carbon, preventing the precipitation of chromium
carbide from the material, which in turn limits chromium depletion and susceptibility to corrosion. A 316Ti alloy can
be held at much higher temperatures far longer before sensitization occurs than can a non-stabilized alloy like 304L.

As to ease of installation, a 25-foot coil of Olympia Chimney Supply's 6" 316Ti Forever Flex liner weighs less than 30 lbs.
The same size coil of the same manufacturer's 304L Armor Flex liner weighs over 100 lbs!
 
If all of that is true why is it that I see a higher percentage of light wall 316ti liners burn out that the 304 heavy wall liners that we install?

I also have another question about some info on your website. It is concerning the info about insulation. In that section you say that insulation is not required if you have the required clearance. But you are talking about forever flex liners which are made by olympia. Olympia very clearly says that you need to insulate their liners when used with solid fuel to maintain the ul listing. And installing a listed product in a way that does not conform to its listing violates code. So how is the info on your site accurate?
 
As to ease of installation, a 25-foot coil of Olympia Chimney Supply's 6" 316Ti Forever Flex liner weighs less than 30 lbs.
The same size coil of the same manufacturer's 304L Armor Flex liner weighs over 100 lbs!
I have installed hundreds of armor flex liners for wood and hundreds of light wall liners some times forever flex some times ventinox for oil and gas. And I would much rather deal with the extra weight than a less flexible liner with a memory that wants to dig into the side of the chimney. But that is personal preference. But you cannot deny that heavy wall is more durable because of the extra thickness and you have the benefit of a smooth wall.
 
I also have another question about some info on your website. It is concerning the info about insulation. In that section you say that insulation is not required if you have the required clearance. But you are talking about forever flex liners which are made by olympia. Olympia very clearly says that you need to insulate their liners when used with solid fuel to maintain the ul listing. And installing a listed product in a way that does not conform to its listing violates code. So how is the info on your site accurate?

We deal with five different code authorities in our service area, and all five are in agreement on this point. If you already have a code-approved chimney and are installing a stainless liner simply to improve updraft or make sweeping easier, the UL 1777 listing isn't required, and the insulation can be omitted.

If any of the code violations listed on our website exist, the UL 1777 listing is required, so the liner must be insulated.
 
We deal with five different code authorities in our service area, and all five are in agreement on this point. If you already have a code-approved chimney and are installing a stainless liner simply to improve updraft or make sweeping easier, the UL 1777 listing isn't required, and the insulation can be omitted.
So they are fine with you ignoring R1003.11.1?

And they are ok with you disregarding the manufacturers instructions listed here?
http://www.olympiachimney.com/insulation
 
Sorry the correct code is R1003.12.1 not 11.1
 
Photocopied from the Forever Flex Liner installation manual:

ffinsulationreq.jpg
 
Photocopied from the Forever Flex Liner installation manual:
Linked from their site
http://www.olympiachimney.com/insulation
are you denying that they are very clearly saying that you need insulation for their liners to be ul listed for use with solid fuel? In addition have you asked them personally about it?

Now isn't it also true that R1003.12.1 requires you install any listed lining material in accordance with its listing?

I have had this argument with others and I believe it applies to all ul listed liners but it without question covers Olympia's liners
 
Any conclusion to this?
 
I can only summarize the points I've tried to make above.
* Olympia Chimney's Forever Flex liner was tested to the UL 1777 standard, and received a listing.
* Details of this listing don't appear on Olympia Chimney's website, which is geared for the consumer.
* Details of this listing do appear in the installation manual for installers and code inspectors to refer to.
* According to the installation manual, insulation is not required for liners installed in chimneys which meet existing codes.
 
Thanks. I just started a thread on this because I could not return to this one for some reason. https://www.hearth.com/talk/threads...a-flexible-liner-that-is-the-question.156513/

I have been debating the use of insulation and I have received mixed opinions from the sales reps. It seems that insulation is required from most insurance companies to maintain safe clearances rather than stack temp and creosote- although stack temps and minimizing creosote formation is important to maintaining a safe chimney. I do know that an item MUST be installed in accordance with the manufacturer’s installation instructions to maintain the item's listings and codes. From what I have been reading recently, the insulation is required in masonry non-lined chimneys and lined chimney’s (no cracks) if the chimney has 4 inches or less thick and contacts a combustible material. So, a properly code compliant chimney, with no cracks and more than 4 inches of concrete is all right to use without insulation. The insulation provides the 1" clearance and zero rating to the 4 inch or less masonry in case the SS liner is in contact with the masonry. Duraflex has a 1 inch spacer clamp (assumed to be used with Thermix pour in insulation) to provide a 1 inch spacing. The clamps are placed every 5 feet of length. One article says that most pour-in insulation jobs are not performed correctly, and make a deteriorated liner very difficult to remove. http://www.chimneys.com/articles/listed-chimney-liner-insulation-that-doesnt-work
 
I can only summarize the points I've tried to make above.
* Olympia Chimney's Forever Flex liner was tested to the UL 1777 standard, and received a listing.
* Details of this listing don't appear on Olympia Chimney's website, which is geared for the consumer.
* Details of this listing do appear in the installation manual for installers and code inspectors to refer to.
* According to the installation manual, insulation is not required for liners installed in chimneys which meet existing codes.
I agree the install manual says what you claim but they also say the opposite on their site. And considering the fact that a very small percentage of chimneys actually have the proper clearance and the improved performance offered by insulating I say always insulate regardless of code. Which to me clearly indicates insulation as well.
 
Any conclusion to this?
The conclusion is that olympia has contradicting info. But a chimney will always be safer and perform better with an insulated liner in it.

if the chimney has 4 inches or less thick and contacts a combustible material.
Your chimney needs to have at least 4" nominal which is actually 3.5" of masonry to be usable even with an insulated liner if it is less that that it is unusable
The insulation provides the 1" clearance and zero rating to the 4 inch or less masonry in case the SS liner is in contact with the masonry.
No it provides zero clearance from the liner to the masonry and zero clearance from the masonry to combustibles.

. One article says that most pour-in insulation jobs are not performed correctly, and make a deteriorated liner very difficult to remove
I would say yes many are not done right but I have pulled quite a few liners out of pour in insulation and while it is harder than a wrapped liner it is defiantly possible.
.
 
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