Transition from capped masonry chimney to class A

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bkoltai9

Member
Nov 23, 2014
23
Oxford, MS
Hi everyone. I've posted a few questions already regarding my install plan and I'm getting very close to figuring it out. Thanks to everyone who has helped me already.

I have a cutoff masonry chimney with a new metal roof overhead. I'm planning to line the masonry chimney and transition to an 8-10' run of class A (Duratech) through the roof.

Duratech makes a transition anchor plate for this purpose.
http://www.homeclick.com/m-and-g-duravent-6dt-ap17x21-17-x-21-transition-anchor-plate/p-76386.aspx

The anchor plate must be used with a slip connector and hanger to suspend the liner.
http://www.efireplacestore.com/cpf-69214.html

I spoke with mg duravent tech support this morning who told me the transition anchor plate must be used with duraliner rigid chimney liner, that they don't make full length flex liner.

I would much prefer to use flex king HD, which appears to be a superior chimney liner product.
http://www.chimneylinerdepot.com/store/5117/product/Flex-King-HD-Chimney-Liner-6X20-Tee-Kit.html

Can anyone tell me if the flex king HD will be compatible with the duratech transition anchor plate and slip connector and hanger? Are there additional pieces or supplies I might need to make the transition?

Thanks everyone :)
 
Hi everyone. I've posted a few questions already regarding my install plan and I'm getting very close to figuring it out. Thanks to everyone who has helped me already.

I have a cutoff masonry chimney with a new metal roof overhead. I'm planning to line the masonry chimney and transition to an 8-10' run of class A (Duratech) through the roof.

Duratech makes a transition anchor plate for this purpose.
http://www.homeclick.com/m-and-g-duravent-6dt-ap17x21-17-x-21-transition-anchor-plate/p-76386.aspx

The anchor plate must be used with a slip connector and hanger to suspend the liner.
http://www.efireplacestore.com/cpf-69214.html

I spoke with mg duravent tech support this morning who told me the transition anchor plate must be used with duraliner rigid chimney liner, that they don't make full length flex liner.

I would much prefer to use flex king HD, which appears to be a superior chimney liner product.
http://www.chimneylinerdepot.com/store/5117/product/Flex-King-HD-Chimney-Liner-6X20-Tee-Kit.html

Can anyone tell me if the flex king HD will be compatible with the duratech transition anchor plate and slip connector and hanger? Are there additional pieces or supplies I might need to make the transition?

Thanks everyone :)
 
I am more familiar with the Selkirk transition Anchor Plates than Dura vent, but I believe that Dura vent uses a slip connector with the Transition Anchor Plate. The slip connector will slide through the plate, and the lower end slides into the liner and held in place with the hanger and clamp. The upper portion of the slip connector then will attach to the pipe.
I assume that any flex liner that has the same ID will connect to the slip connector, whether it is Dura liner or Flex Pro.
 
After speaking with both duravent and flex king tech support, both told me that mix and match is a bad idea and will void all warranties.

So that probably takes duravent out of the equation since I don't like the look of their duraliner rigid system.

I found Olympia has a transition anchor plate that goes from their Ventis class a chimney to any of their flex or rigid liners. Are these good products? I see armorflex is even thicker than flex king HD. I have a straight shot, so maybe this would be a good product for me?

Double D, I saw you mentioned Selkirk transition anchor plate, but I can't find any info online. I've read metalbestos is a good class A chimney but I don't know anything about their liners.

I'm looking for recommendations.
 
Go with the insulated double wall rigid if you can afford the extra bucks, it is excellent stuff, drafts great and cleans easy.
I have it, and love it. I used a pc of Duravent flex at the bottom to get from the first flue tile though the smokes shelf and damper to the stove outlet. The rigid and flex mate perfectly.
Don't be afraid of rigid, it is already insulated and I installed myself. Just my opinion, but I feel it is stronger and more durable then flex, and again, easier to clean.
 
I found Olympia has a transition anchor plate that goes from their Ventis class a chimney to any of their flex or rigid liners. Are these good products? I see armorflex is even thicker than flex king HD. I have a straight shot, so maybe this would be a good product for me?
We use pretty much all olimpia products now and we have been very happy with them and yes for wood liners we always use armor flex it is a very good product. And ventis is pretty good as well the only thing is their joints slip together and then get screwed which some people don't like. i prefer it over twist lock but that is just me


but I feel it is stronger and more durable then flex, and again, easier to clean.
Heavy flex like the armor flex takes care of those problems. The only problem i have with the duravent Sorry meant dura liner system is the galvanized exterior. That worries me a bit but i might be crazy.
 
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We use pretty much all olimpia products now and we have been very happy with them and yes for wood liners we always use armor flex it is a very good product. And ventis is pretty good as well the only thing is their joints slip together and then get screwed which some people don't like. i prefer it over twist lock but that is just me



Heavy flex like the armor flex takes care of those problems. The only problem i have with the duravent system is the galvanized exterior. That worries me a bit but i might be crazy.
They make a galv outside and a s.s. outside shell. I went with galv for cost reasons, and have not had an issue yet in 9 years. The only thing on the outer shell I have that I don't like is the black staining from the exhaust gases. Guess I could try and clean it and paint it some year.
 
They make a galv outside and a s.s. outside shell. I went with galv for cost reasons
Cool i hadn't seen that they had a ss outer wall that changes things. Did they add it recenty i looked at their catalog last year and all they had listed I meant dura liner not dura vent sorry. Is dura liner available with ss outer wall to?
 
They make a galv outside and a s.s. outside shell. I went with galv for cost reasons, and have not had an issue yet in 9 years. The only thing on the outer shell I have that I don't like is the black staining from the exhaust gases. Guess I could try and clean it and paint it some year.
Dont you have a duraliner lined chimney or am i thinking of someone else?
 
Cool i hadn't seen that they had a ss outer wall that changes things. Did they add it recenty i looked at their catalog last year and all they had listed I meant dura liner not dura vent sorry. Is dura liner available with ss outer wall to?
It was when I ordered my DuraLiner system, but that was back in 2006. Of course it was more expensive. Think I paid around $900 or so back then. But back then flex was actually costlier than it seems now. WHen I preiced the flex and insulation, it was only a couple hundred dollars difference.
I got it all of Ventingpipe.com.
Hope they didn't discontinue, I was thinking of replacing the stuff out of the top of the old masonry with s.s. outer shell stuff.
 
Hope they didn't discontinue, I was thinking of replacing the stuff out of the top of the old masonry with s.s. outer shell stuff.
I am not sure we dont really deal with simpson stuff much we have run into some quality control issues with them in the past and stopped using their stuff. That may have changed now though
 
I don't know who the original poster talked to, but DurVent flex comes in 15, 20, 25 & 30 foot lengths.
Here is a kit for 30' with the top plate, cap & connect for a decent price I think
http://www.ventingpipe.com/duravent...wall-30-basic-kit-includes-top-plate/p1760605
'
Also looks like they only offer the galvalume outer shell now. Could do a transitional top plate and put class A up top, that would be s.s. inner & outer or galvalume outer s.s. inner, they still offer both for that.
The flex is 1" clearance to masonry, or 0 clearance with insulation
Double wall rigid is 0 clearance to masonry, and 0 to masonry & 0 to masonry to combustibles.
 
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Duravent tech support told me transition anchor plate with the slip connector and hanger is specifically for the duraliner system and not for duraflex. I've been looking into the duraliner system and it seems to be a solid product. I was turned off by having to rivet the pieces together, but I suppose that's probably not really a big deal. I didn't realize when I first posted that it was factory insulated, which seems pretty nice.

I'm concerned about the size of the transition anchor plate. The biggest one from Duravent is 17x21. My masonry flue has a 13x18 opening and the exterior dimensions are 21x26. 17x21 will only cover about 2 inches of the brick on eash side and I wonder if that is enough to both suspend the duraliner and support the duratech.
 
I'm concerned about the size of the transition anchor plate. The biggest one from Duravent is 17x21. My masonry flue has a 13x18 opening and the exterior dimensions are 21x26. 17x21 will only cover about 2 inches of the brick on eash side and I wonder if that is enough to both suspend the duraliner and support the duratech.
Then add some steel angle iron or something under it to add support. Personally i would go with the olympia stuff but i am partial to their stuff i am sure the simpson stuff will work fine but i would go with a heavier liner than the dura vent if i was doing it
 
Riveting pieces together is quick with the right tools. Get a decent pop-rivet gun. DuraLiner is an excellent product. It will stand up well. Hogwildz system is done with DuraLiner. He may be able to give you some installation tips.

I had the same concerns as you about supporting the top plate with a very large opening and voiced it earlier. Perhaps an option would be to have an 3/16" steel top plate fabricated that covers the top, say 20 x 25, with a hole cut in the middle to clear the pipe. This would get sealed with silicone and anchored to the chimney.
 
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The pop rivets are S.S.
Make sure you use a good pop rivet gun.
There is no drilling, the rigid is pre drilled, ready to be fit together and 4 pops per seam.
It ain't going anywhere.
 
They are the rivets that come with it.
This is the lesser of the evils.
At worst the outer shell may be affected, but the inner shell of the liner unaffected.

Being a liner situation, with really no outside elements to contend with, there really is not much to worry about.
If this was an issue, there would be many warranty issues, which would bee all over here and elsewhere.
 
They tell you to use ss rivets on a galvanized shell????? Not a very good idea
Can you explain that concern? We used zinc + stainless frequently in steel boat building in the highly corrosive salt water environment. Zinc was the ideal sacrificial element. I used it under stainless stanchion pads to prevent steel corrosion from the tapped in holes. Saw the boat last year and there still was no corrosion.
 
an you explain that concern? We used zinc + stainless frequently in steel boat building in the highly corrosive salt water environment. Zinc was the ideal sacrificial element. I used it under stainless stanchion pads to prevent steel corrosion from the tapped in holes. Saw the boat last year and there still was no corrosion.
I was told you could get a galvanic reaction between the 2 but i am no metallurgist i only know what i have been taught that could be wrong
 
Stainless is a fairly noble metal. I think this is a non-issue.
 
From what I ready, the reaction is minimal is any, and would be towards the galv of course, not the S.S.
Te least of any of the evils. Not much other choices.
 
Before i posted that i did a quick search and found allot of stuff about galvanic reactions between ss and galvanized so i think it could be an issue i just don't know how big of one it is
 
I would much rather have stainless rivets than regular steel in this application. Maybe contact DuraVent if concerned?

"...when using a bare steel plate with a zinc rivet, the ratio of the cathode surface area to the anode surface area is large, and the rivet will fail rapidly because of accelerated corrosion. When combining a zinc plate with a stainless steel rivet, the area ratio between the cathode and anode is reversed, and although more surface area is affected, the depth of penetration is small; the fastener should not fail because of corrosion."
http://www.galvanizeit.org/hot-dip-galvanizing/how-long-does-hdg-last/in-contact-with-other-metals
 
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"...when using a bare steel plate with a zinc rivet, the ratio of the cathode surface area to the anode surface area is large, and the rivet will fail rapidly because of accelerated corrosion. When combining a zinc plate with a stainless steel rivet, the area ratio between the cathode and anode is reversed, and although more surface area is affected, the depth of penetration is small; the fastener should not fail because of corrosion.
ok then
 
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