Duraplus Insulated triple wall running through masonry chimney

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Caught.the.flue

New Member
Jan 28, 2018
7
Placerville, California
I've been an avid reader of many a post on hearth.com, but today I finally made the leap and created an account! Here's my first post...

A year ago when I purchased my first house, an 1890s era farmhouse, that has been built on and expanded over the years, I noticed the wonderful old fireplace was covered up by a terrible propane insert. 34k BTUs and it would run me an arm and a leg just to keep the house at 55 degrees (Fahrenheit). After one winter that had to go. Underneath I found what I later learned was an old Heatform unit. Probably installed in the 60s or 70s, seeing as it was still in pretty good condition. After peeking down the chimney and looking for creosote buildup, brazing a plate over a hole they drilled for a half inch gas line, and patching the cinderblock exterior, I was ready to burn. Mind you, being somewhat new to an open fireplace, I was in awe of the wood that thing would gobble up. I was burning a cord of wood a month, and again, barely keeping the house at 55. Then came the day when the creosote (after just three months) built up so much that my draft reversed. My goodness, smoke is not the greatest when it's in every room of your house. Enter hours upon days of research, and after realizing that building a RMH was out of my budget and time frame, I figured I'd settle for a wood burning insert. I found a reasonably priced Jotul c450 on Craigslist, that an older couple (who were switching to gas) were willing to part with. They even had a hoist to drop it into my little 1982 Toyota pickup. It came complete with chimney cap and some silly single ply stainless duraflex liner that was half the length I needed. I was ready to start the great adventure of installing it.

I painters tape tented some clear poly around the fireplace. Grabbed my trusty sawsall and grinder, and started going to town. Most of my day later I emerged victorious with 2 steel tubes, 2 halves of a damper plate, and some other chunks of steel and brick that had to come out. I had a hole big enough for my 6 inch flex.

Turns out... That was the moment I realized I was going to need something with far superior insulation than stainless flex on my completely shaded exterior 20ft tall chimney.

I called local fireplace shops, and they wanted to sell me on double wall for almost the same price I got the insert for! I did a bit more research, found out my local orange box has some duravent triple wall (3 separate pipes, the second one wrapped with ceramic insulation) that measured 10 inches across with the interior being my desired 6 inch. It was almost half the price. I just grabbed the couplers off the flex, and started assembling. Mind you. My wife is great at many things. Standing on a roof with me and holding up 90lbs of chimney would not be one of them. So I had to improvise. The outer layer of the triple wall is basically just an insulating layer of air, so I didn't feel bad drilling and mounting steel hanger straps to it. Couple of piece of wood and I had a solid hoist to lower it down one 3 ft piece at a time.

I used some couplers/adapters that came with my insert to run 4 feet of flex and attach it to the new triple wall, and started the arduous journey of screwing the hanger straps down to my wood blocks, attaching the next section, unscrewing, lowering it down, screwing it back in. Piece by piece, all by myself! Then I fashioned some brackets to bolt the straps on, to provide support from the top (remember 90ish lbs). Oh what a great feeling when you're done on the roof. Hopefully I can get the 2 inches of lift I need with the flex to install the stove collar, because I liberally Siliconed (high temp of course) the flashing plate to the clay flue tiles.

So here's where I sit, or stand, as of today. I've accomplished something I'm not sure I've seen or heard of being done before. I'm looking for input before I actually install the stove down below. Did I accomplish something crazy and terrible, or borderline genius and awesome? Sometimes I have trouble telling the two apart.
 

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zig

Burning Hunk
Oct 10, 2014
223
Caro MI.
I did the same thing you did except double wall and 16ft. of pipe but it's still heavy. 1/4 inch steel plate on the bottom where the 12x12 terracotta sits as the chimney was made for a slammer install popular way back when and a big open hearth for a stove to sit into, really works well holding the weight. I was concerned about condensation inside the terracotta because it's an outside chimney but I haven't had a problem. The triple-wall you used made me wonder about it on yours but the chimney looks to be interior so you should be ok. It will work fine and clean very easily.
 

saewoody

Feeling the Heat
Feb 15, 2017
456
CT
I don’t have any specific advice for you, but I enjoyed the read. Sounds like quite the achievement! Hope it works out well. Thanks for sharing.


Sent from my iPhone using Tapatalk
 

webby3650

Master of Fire
Sep 2, 2008
11,061
Indiana
Typically anything that isn’t SS will not hold up inside a flue. Things tend to rust beyond belief...
Did you price a liner kit with insulation? They can be bought relatively inexpensively on-line.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
I've been an avid reader of many a post on hearth.com, but today I finally made the leap and created an account! Here's my first post...

A year ago when I purchased my first house, an 1890s era farmhouse, that has been built on and expanded over the years, I noticed the wonderful old fireplace was covered up by a terrible propane insert. 34k BTUs and it would run me an arm and a leg just to keep the house at 55 degrees (Fahrenheit). After one winter that had to go. Underneath I found what I later learned was an old Heatform unit. Probably installed in the 60s or 70s, seeing as it was still in pretty good condition. After peeking down the chimney and looking for creosote buildup, brazing a plate over a hole they drilled for a half inch gas line, and patching the cinderblock exterior, I was ready to burn. Mind you, being somewhat new to an open fireplace, I was in awe of the wood that thing would gobble up. I was burning a cord of wood a month, and again, barely keeping the house at 55. Then came the day when the creosote (after just three months) built up so much that my draft reversed. My goodness, smoke is not the greatest when it's in every room of your house. Enter hours upon days of research, and after realizing that building a RMH was out of my budget and time frame, I figured I'd settle for a wood burning insert. I found a reasonably priced Jotul c450 on Craigslist, that an older couple (who were switching to gas) were willing to part with. They even had a hoist to drop it into my little 1982 Toyota pickup. It came complete with chimney cap and some silly single ply stainless duraflex liner that was half the length I needed. I was ready to start the great adventure of installing it.

I painters tape tented some clear poly around the fireplace. Grabbed my trusty sawsall and grinder, and started going to town. Most of my day later I emerged victorious with 2 steel tubes, 2 halves of a damper plate, and some other chunks of steel and brick that had to come out. I had a hole big enough for my 6 inch flex.

Turns out... That was the moment I realized I was going to need something with far superior insulation than stainless flex on my completely shaded exterior 20ft tall chimney.

I called local fireplace shops, and they wanted to sell me on double wall for almost the same price I got the insert for! I did a bit more research, found out my local orange box has some duravent triple wall (3 separate pipes, the second one wrapped with ceramic insulation) that measured 10 inches across with the interior being my desired 6 inch. It was almost half the price. I just grabbed the couplers off the flex, and started assembling. Mind you. My wife is great at many things. Standing on a roof with me and holding up 90lbs of chimney would not be one of them. So I had to improvise. The outer layer of the triple wall is basically just an insulating layer of air, so I didn't feel bad drilling and mounting steel hanger straps to it. Couple of piece of wood and I had a solid hoist to lower it down one 3 ft piece at a time.

I used some couplers/adapters that came with my insert to run 4 feet of flex and attach it to the new triple wall, and started the arduous journey of screwing the hanger straps down to my wood blocks, attaching the next section, unscrewing, lowering it down, screwing it back in. Piece by piece, all by myself! Then I fashioned some brackets to bolt the straps on, to provide support from the top (remember 90ish lbs). Oh what a great feeling when you're done on the roof. Hopefully I can get the 2 inches of lift I need with the flex to install the stove collar, because I liberally Siliconed (high temp of course) the flashing plate to the clay flue tiles.

So here's where I sit, or stand, as of today. I've accomplished something I'm not sure I've seen or heard of being done before. I'm looking for input before I actually install the stove down below. Did I accomplish something crazy and terrible, or borderline genius and awesome? Sometimes I have trouble telling the two apart.
It should work but it is not an approved or code compliant install. Also you said you wanted more insulation than an insulated flex liner would provide. But the triple wall you used has exactly the same 1/2" ceramic wool insulation used on liners. Like i said it will work fine but you didnt really gain anything by going this route over a good insulated liner.
 

Caught.the.flue

New Member
Jan 28, 2018
7
Placerville, California
In this case it's what was available at the parts store on the day I needed it. That's the driving force behind most of the materials I source. This being the stove shops didn't have insulated flex in stock, and I go weeks between having time to work on projects. As far as rust, the double wall hard pipes that most stove shops tout is stainless interior, with a galvanized exterior pipe anyway from what I've seen. I figure with my lack of block off plate the inside of the chimney will heat up anyway to reduce any moisture buildup. This was my way to over-engineer and cut costs in one. The insulated flex liner would have run me 500 minimum, whereas I spent 400 on my entire setup this way, with the added benefit of an easy to sweep, well supported inner structure. As far as the code compliance comment, I would love to see a copy of any NFPA code that says as much. I do intend to sell this house eventually with detailed documentation and pictures of all projects I've done. So if I'm in violation of any code I would like to see it in writing and mark it on the checklist of to-dos before selling. This is the same class a chimney pipe they allow you to run in walls or attics with a 2 inch air gap to any combustibles. Exactly because the stainless interior is rated to 2100 degrees in case of chimney fire. Here's some pictures of the final results! Cheers.
 

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bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
In this case it's what was available at the parts store on the day I needed it. That's the driving force behind most of the materials I source. This being the stove shops didn't have insulated flex in stock, and I go weeks between having time to work on projects. As far as rust, the double wall hard pipes that most stove shops tout is stainless interior, with a galvanized exterior pipe anyway from what I've seen. I figure with my lack of block off plate the inside of the chimney will heat up anyway to reduce any moisture buildup. This was my way to over-engineer and cut costs in one. The insulated flex liner would have run me 500 minimum, whereas I spent 400 on my entire setup this way, with the added benefit of an easy to sweep, well supported inner structure. As far as the code compliance comment, I would love to see a copy of any NFPA code that says as much. I do intend to sell this house eventually with detailed documentation and pictures of all projects I've done. So if I'm in violation of any code I would like to see it in writing and mark it on the checklist of to-dos before selling. This is the same class a chimney pipe they allow you to run in walls or attics with a 2 inch air gap to any combustibles. Exactly because the stainless interior is rated to 2100 degrees in case of chimney fire. Here's some pictures of the final results! Cheers.
You dont need a code book. The code book says you have to follow manufacturers instructions. And there is nothing in the duravent manual that says you can install it inside a chimney or hang it from strapping at the top or transition to flex at the bottom. Like i said before it should work fine. But i also wanted to make it very clear to anyone reading this that this is not a code compliant install. What double wall are you referring to thgat most stove shops tout?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
Again to be clear as long as it is supported well enough and the connection to the flex is done the right direction and securely i see no safety issue at all. But you are using a ul listed product in a way it is not intended to be used that meand the install cannot meet code.
 

HomeinPA

Minister of Fire
Jan 4, 2018
510
Central PA
In this case it's what was available at the parts store on the day I needed it. That's the driving force behind most of the materials I source. This being the stove shops didn't have insulated flex in stock, and I go weeks between having time to work on projects. As far as rust, the double wall hard pipes that most stove shops tout is stainless interior, with a galvanized exterior pipe anyway from what I've seen. I figure with my lack of block off plate the inside of the chimney will heat up anyway to reduce any moisture buildup. This was my way to over-engineer and cut costs in one. The insulated flex liner would have run me 500 minimum, whereas I spent 400 on my entire setup this way, with the added benefit of an easy to sweep, well supported inner structure. As far as the code compliance comment, I would love to see a copy of any NFPA code that says as much. I do intend to sell this house eventually with detailed documentation and pictures of all projects I've done. So if I'm in violation of any code I would like to see it in writing and mark it on the checklist of to-dos before selling. This is the same class a chimney pipe they allow you to run in walls or attics with a 2 inch air gap to any combustibles. Exactly because the stainless interior is rated to 2100 degrees in case of chimney fire. Here's some pictures of the final results! Cheers.

Yet another homeowner who knows more than all the professionals combined on here! I love it.

If you have all the answers why do you come on here and ask questions? We, the collective "we" on here, who do this for a living and are here to help keep people from making an ash of themselves have forgotten more than you'll know and yet you have the audacity to suggest that bholler and the rest of us who are reading along and marveling at your "ingenuity", don't know our ass from a hole in the ground?! Here's the deal Skippy, IF, and God forbid when, you ever have a problem with that nstallation for some reason and the insurance company can put 2 & 2 together (that might be your out right there), they can deny your claim because you chose to cut corners and not do it to code. And I can damn sure assure you that any legitimate, moderately intelligent sweep who ever comes to inspect that for any reason let alone a real estate inspection will catch it and write it up as non-compliant and then you'll wish you had listened to bholler and taken the extra time to do it right.
 
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Caught.the.flue

New Member
Jan 28, 2018
7
Placerville, California
I was trying to ask politely. A professional in any field would have a copy of a code book from the NFPA. Not being a chimney sweep, I happen to lack one in this case. I honest to goodness wouldn't want to do anything unsafe in my home. All the stove shops I talked to couple 5 feet of stainless flex to double wall duravent pipe, I figured one extra layer can't be that big of a deal. The support system was just my way of accomplishing it as a one man job. The hard pipe is resting on brick for support at the base I may be 'just another homeowner' but when I do something, I set out to do it with thought. Its not like I tossed in the first slammer I happened across on Craigslist...
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
I was trying to ask politely. A professional in any field would have a copy of a code book from the NFPA. Not being a chimney sweep, I happen to lack one in this case. I honest to goodness wouldn't want to do anything unsafe in my home. All the stove shops I talked to couple 5 feet of stainless flex to double wall duravent pipe, I figured one extra layer can't be that big of a deal. The support system was just my way of accomplishing it as a one man job. The hard pipe is resting on brick for support at the base I may be 'just another homeowner' but when I do something, I set out to do it with thought. Its not like I tossed in the first slammer I happened across on Craigslist...
Well yes of course i have a copy of nfpa. But what you would want is irc. And all tgat saus is that all ul listed components need to be installed according to their listing. So no it doesnt meet code. It could still be perfectly safe but if there ever is an issue requiring insurance you may have problems.
 

HomeinPA

Minister of Fire
Jan 4, 2018
510
Central PA
Well yes of course i have a copy of nfpa. But what you would want is irc. And all tgat saus is that all ul listed components need to be installed according to their listing. So no it doesnt meet code. It could still be perfectly safe but if there ever is an issue requiring insurance you may have problems.

There are loads of things we see out here that could be considered safe but in these days when most everyone's first thought when something goes sideways is "Who can I sue?", we don't have the luxury of telling people that it'll work. We document and advise when we can clearly see an issue and what you the homeowner do after that is up to you .
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
There are loads of things we see out here that could be considered safe but in these days when most everyone's first thought when something goes sideways is "Who can I sue?", we don't have the luxury of telling people that it'll work. We document and advise when we can clearly see an issue and what you the homeowner do after that is up to you .
I agree and i would never do work like this. But if i was calledto clean it i would inform them it wasnt to code but i would not hesitate to wor k on it from what i have seen because i see no imminent danger. Now in person i may see something that is unsafe.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,548
South Puget Sound, WA
But if i was calledto clean it i would inform them it wasnt to code but i would not hesitate to wor k on it from what i have seen because i see no imminent danger. Now in person i may see something that is unsafe.
Thanks for that clarification. I think this is the first time we've had an installation like this posted. Although I would not advise this type of installation, assuming that the OP has done diligence and safely installed the assembly it sounds serviceable. The installation sounds similar to a chased chimney, except with a masonry chase in this case. User fabricated supports are sometimes necessary for supporting metal chimneys. For example, a bracket extension to get out past an eave, or a user-made brace. Flex can tied to class A when a masonry chimney extension is added.
 
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bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
Thanks for that clarification. I think this is the first time we've had an installation like this posted. Although I would not advise this type of installation, assuming that the OP has done diligence and safely installed the assembly it sounds serviceable. The installation sounds similar to a chased chimney, except with a masonry chase in this case. User fabricated supports are sometimes necessary for supporting metal chimneys. For example, a bracket extension to get out past an eave, or a user-made brace. Flex can tied to class A when a masonry chimney extension is added.
Yes i didnt think about flex to class a in that instance. And i have done it lol. So there is a proper fitting made to do it.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,548
South Puget Sound, WA
What's unusual in this installation is that all three customizations are in one install.
 

Caught.the.flue

New Member
Jan 28, 2018
7
Placerville, California
For the record, I believe I used the correct duravent stainless couplers, all pointing in the right direction (so creosote will in theory not be able to leak out of the pipe), all fittings predrilled with 3 stainless screws evenly spaced to create a secure connection. And I was able push my 6 inch sweep through from one end to the other and into my stove with the damper removed. No part of my flex is deformed or not fully seated into its coupler. And when I was brainstorming this project, I was figuring that the perfectly intact masonry chimney was in fact exactly that, a chase. I'm sure that those pipes need to be strapped and supported somehow, so ya I kind of freehanded that one, not knowing how those in the industry would accomplish it. I just figured that people hadn't tried this before, because I don't think many have a whopping 11 1/2 inch by 14 inch chimney.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
For the record, I believe I used the correct duravent stainless couplers, all pointing in the right direction (so creosote will in theory not be able to leak out of the pipe), all fittings predrilled with 3 stainless screws evenly spaced to create a secure connection. And I was able push my 6 inch sweep through from one end to the other and into my stove with the damper removed. No part of my flex is deformed or not fully seated into its coupler. And when I was brainstorming this project, I was figuring that the perfectly intact masonry chimney was in fact exactly that, a chase. I'm sure that those pipes need to be strapped and supported somehow, so ya I kind of freehanded that one, not knowing how those in the industry would accomplish it. I just figured that people hadn't tried this before, because I don't think many have a whopping 11 1/2 inch by 14 inch chimney.
The bottom adapter that we can see is not the right component for that liner. Lightwall liners should never be attached with screws they simply will not hold. The component for lightwall should have a band clamp on it to secure it to the liner.

Yes many people have done this but generally not with the lower quality triple wall. The times i have seen it done it was done with insulated double wall chimney. But that does not change the fact that the pipe is not being used in an approved environment and is not supported as required. Therefore it does not meet the requirements of the listing and that means it doesnt meet code
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
Also I'm curious what a masonry chimney extension is, maybe you could elaborate?
That is using class a chimney ontop of a masonry chimney that needs more height. There are different plates made for if you are extending a chimney with a clay liner or if you are extending one with a stainless liner.
 
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Mark8

Member
Dec 23, 2017
248
Central California
Yet another homeowner who knows more than all the professionals combined on here! I love it.

If you have all the answers why do you come on here and ask questions? We, the collective "we" on here, who do this for a living and are here to help keep people from making an ash of themselves have forgotten more than you'll know and yet you have the audacity to suggest that bholler and the rest of us who are reading along and marveling at your "ingenuity", don't know our ass from a hole in the ground?! Here's the deal Skippy, IF, and God forbid when, you ever have a problem with that nstallation for some reason and the insurance company can put 2 & 2 together (that might be your out right there), they can deny your claim because you chose to cut corners and not do it to code. And I can damn sure assure you that any legitimate, moderately intelligent sweep who ever comes to inspect that for any reason let alone a real estate inspection will catch it and write it up as non-compliant and then you'll wish you had listened to bholler and taken the extra time to do it right.

You sir really need to come down to earth and put into perspective the importance of your trade and your relevance on this planet. YEA, professional mason, professional chimney sweep, professional plumber, professional trash man, professional postal employee, professional cook, professional dog chit picker upper, LOL. Get a grip little boy, when it's all said and done you will just become worm food like everyone else.

I see this forum is geared towards the collective "we" stroking your own egos, believe me, there are thousand of other monkeys out there doing exactly the same kind of work you do in the construction trade every day. So you are no genius by any means.

When you can invent a technology that nobody else has invented, only then you should stick out your chest and toot your own horn, but for now your just repeating what thousands before you have done, and it's really not that impressive.
 
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Jan Pijpelink

Minister of Fire
Jan 2, 2015
1,945
South Jersey
You sir really need to come down to earth and put into perspective the importance of your trade and your relevance on this planet. YEA, professional mason, professional chimney sweep, professional plumber, professional trash man, professional postal employee, professional cook, professional dog chit picker upper, LOL. Get a grip little boy, when it's all said and done you will just become worm food like everyone else.

I see this forum is geared towards the collective "we" stroking your own egos, believe me, there are thousand of other monkeys out there doing exactly the same kind of work you do in the construction trade every day. So you are no genius by any means.

When you can invent a technology that nobody else has invented, only then you should stick out your chest and toot your own horn, but for now your just repeating what thousands before you have done, and it's really not that impressive.

I understand what you say here. The OP has done something we do not see everyday. Both @HomeinPA and @bholler are trying to explain to the OP his install is not according to code and he is taking some risks in case something goes wrong and he might not get his insurance company helping him. However, I agree that @HomeinPA could have been more gentle choosing his words. I am far from an expert, but from what I have learned from this site, I know that what the OP configured is far from regular. Let's keep it civil here.
 
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Mark8

Member
Dec 23, 2017
248
Central California
I understand what you say here. The OP has done something we do not see everyday. Both @HomeinPA and @bholler are trying to explain to the OP his install is not according to code and he is taking some risks in case something goes wrong and he might not get his insurance company helping him. However, I agree that @HomeinPA could have been more gentle choosing his words. I am far from an expert, but from what I have learned from this site, I know that what the OP configured is far from regular.

Yes, we are all adults here, and we fully understand what is being explained, but there is no reason to thrash people. We are just men talking about mechanical things and we should show respect to all. Some people need to get off their high horse.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,480
central pa
Yes, we are all adults here, and we fully understand what is being explained, but there is no reason to thrash people. We are just men talking about mechanical things and we should show respect to all. Some people need to get off their high horse.
You mean like calling those of us in this trade monkeys and saying we are no geniuses?
 
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