# Double Wall vs. Triple Wall Class A Chimney



## Johnny G82 (Oct 3, 2013)

Hi,

I am installing a Hearthstone Phoenix that will be vented out through an exterior wall (I realize that this is not ideal) and then up about 15' through a class A chimney.  My question is, which type of class A chimney will perform best in terms of draft and creosote build up on the exterior?  Double or Triple wall?

I am considering using the AirJet chimney system, but want to make sure that a Triple wall chimney with no insulation won't cause increased creosote build up.  Does anyone have experience with this pipe?

http://www.continentalindustries.com/files/downloads/AJ-2100Brochure.pdf


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## DAKSY (Oct 4, 2013)

It looks like a good product, but the diagram on Page 9 is WRONG. The THREE foot dimension is taken from highest point where the chimney exits thru (or passes along) the roof. Also, I'm not big on Galvanized exterior chimney pipe. I've seen too many instances where the Galvanizing has failed & the pipe has rusted. Your call, tho.


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## dougand3 (Oct 4, 2013)

How much is the AirJet 15' chimney? Compare to Selkirk or Simpson double wall, insulated, SS.


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## blwncrewchief (Oct 4, 2013)

DAKSY said:


> It looks like a good product, but the diagram on Page 9 is WRONG. The THREE foot dimension is taken from highest point where the chimney exits thru (or passes along) the roof. Also, I'm not big on Galvanized exterior chimney pipe. I've seen too many instances where the Galvanizing has failed & the pipe has rusted. Your call, tho.



X2. I really would not want to spend the money to install a chimney that is a galvanized exterior. Especially for a wood stove. As far as the creosote issue since it is a ventilated air gap system cooler flue temps could be an issue and no way to predict without testing data. Since the system is ventilated it is a dynamic system relying on the design of the system versus an insulated double wall is pretty much a static design. It could be better or it could be worse. I would tend to stay with the tried and true insulated double wall SS unless you like to experiment.


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## oldspark (Oct 4, 2013)

I would NOT buy it for the reasons given already, galv. exterior and no insulation=not good as SS with insulation, there is a insulated triple wall on the market if you want that for one reason or another. DuraPlus is the name.
http://www.northlineexpress.com/chi...avent-chimney-pipe/duraplus-chimney-pipe.html


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## begreen (Oct 4, 2013)

I'm not a big fan of triple wall chimney. Air Jet has a larger diameter pipe to do the same job as a more slender insulated double-wall pipe. And the air passages make wonderful homes for wasps and hornets.  I would stick to the major brands for a wider variety of solutions, less bulk, stainless jacket and ease of getting parts. M&G DuraTech, Selkirk SuperVent or Ultra-Temp HT, or ICC Excel are much more common brands with good quality.


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## bag of hammers (Oct 4, 2013)

DAKSY said:


> It looks like a good product, but the diagram on Page 9 is WRONG. The THREE foot dimension is taken from highest point where the chimney exits thru (or passes along) the roof. Also, I'm not big on Galvanized exterior chimney pipe. I've seen too many instances where the Galvanizing has failed & the pipe has rusted. Your call, tho.



They state that " Top of pipe must be 2 ft. higher than anything within 10 ft. of the chimney" which I believe is correct, but then in the diagram it says "if 10' or less, chimney must extend 2' above peak".  I know this is just supposed to be an example where the peak happens to be exactly 10 away, but how often does that really happen?  To my fuzzy brain, the picture at first glance sort of implies that if the chimney is 10' 1" from the peak, then it doesn't matter.   Yeah it's kinda anal, but pictures speak louder than words.   If I wrote the manual, I'd include a 2nd pic / example where the chimney is nowhere near the peak, just to drive the point home.


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## Johnny G82 (Oct 5, 2013)

Thanks for all the replies.  I should have specified in my initial post that they have a stainless steel option that I would go with.  Overall for what I need this setup would price out around $800 which seemed to be about the same as Selkirk's Supervent, and quite a bit less than some of the other more popular brands.  I liked the fact that the Air Jet pipe only needs to protrude 1" inside the interior wall since I'm trying to reduce the clearance from the wall to the stove as much as possible.  I think most of the other systems that I've seen require 2" for Duravent and 3" or more for the other brands. 

It sounds like most of you agree that for an exterior application, I should probably go with an insulated chimney system, so I think that's what I'll do.

Thanks for the good advice.


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## begreen (Oct 5, 2013)

The clearances on the inside wall are determined by the distance of the connector pipe to the nearest combustible, ie: the wall.


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## oldspark (Oct 6, 2013)

Yea the link to the manual states standard 2 inch clearance to combustibles.


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## dougand3 (Oct 6, 2013)

If the price is the same, I'd sure go with Selkirk Supervent. I put it in my house and am quite pleased with it.


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## Johnny G82 (Oct 7, 2013)

Thanks everyone.

I'm sorry if I confused you.  The 3" that I mentioned above was in reference to the distance that Selkirk says the pipe must extend inside the room when installing the horizontal chimney through the wall.  This would then connect to the single or double wall stove pipe from the stove.

Since this pipe is stainless steel, it seems that this would look a bit awkward since it would be visible from the inside of the room.  Has anyone run into this situation? 

I am planning on installing a 1" air shield from the combustible wall, so my other question is if that 3" should be measured from the combusible wall or the air shield?


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## bag of hammers (Oct 7, 2013)

Johnny G82 said:


> Since this pipe is stainless steel, it seems that this would look a bit awkward since it would be visible from the inside of the room.



In some setups the stainless chimney extends into the room.  In my case, Selkirk Supervent that extends several inches down from the support box (for proper clearances from the stove pipe adapter to exposed beam, etc.).  There are a few threads here on painting stainless chimney - I've thought about it and may paint it black one day but the look of the stainless actually doesn't bother me enough to get this on the priority list.  It may be a different perspective in a horizontal install but I'd assume you can shoot some paint on the exposed part if it bugs you enough...?


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## akbear (Oct 7, 2013)

In my case, whether it's right or wrong, I have this adaptor to transition from the chimney to the stove http://www.plumbersurplus.com/Prod/Selkirk-Metalbestos-258240-8-DSP-Chimney-Pipe-Adapter/272840/Cat/353?gclid=CKKaveXohboCFYw1QgodSWsApQ 
(well, a 6 inch size, I see this one linked is 8 ) and the stove collar on mine fits into the recess at least an inch or so.  On the fires that I had so far, I haven't seen any temperatures either on the collar itself or the chimney that would lead me to be concerned with the setup which is why I've now set the magnetic thermometer on top of the chimney attached to the wall trim ring just to monitor it instead of using the IR gun on the pieces often.  (the chimney is reflecting on the back of the stove at the bottom of the picture, so ignore that to save some confusion)


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## goofa (Oct 7, 2013)

ok so if you have no clearance issues inside the home you can use single wall pipe up to the ceiling box or is it more logical to just use the double wall pipe?


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## cableman (Oct 7, 2013)

If using the support box i think that has to be atleast 3" from the ceiling then keep the chimney pipe flush with the finish trim. Not sure of your set up but im in the process of installing mine on a small cathedral ceiling and im thinking thats how its gonna go!


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## oldspark (Oct 7, 2013)

Is that class A he has right up to the stove?


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## akbear (Oct 7, 2013)

oldspark said:


> Is that class A he has right up to the stove?



if you are talking about me, yes, it's class A where it comes out from the wall and the stove collar you are seeing (the transition piece or chimney pipe adaptor between the two which can not be seen), but it might also be notable that this is on a cookstove so by the time the exhaust has reached that point it has travelled across the top of the oven to the other side of the stove and makes a "P" shaped loop either down the back of the oven with the bypass open or down the side of the oven across the bottom and up the back side if the bypass is closed.


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## Johnny G82 (Oct 7, 2013)

Thanks for your help everyone.  

I think the only question I have left is this:
I am planning on installing a 1" air shield off the combustible wall that I am installing my stove in front of.  It will have a 1" air space spaced out with strips of durock and vented top and bottom, with Durock attached to the strips. If Selkirk is saying the horizontal chimney pipe must extend through the wall and into the room 3", should I measure that 3" from the combustible wall or from the air shield surface (durock)?


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## begreen (Oct 7, 2013)

The clearance measurement is always to the nearest combustible, in this case the combustible wall.


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## Johnny G82 (Oct 7, 2013)

Ok, thanks begreen.  The Selkirk installation manual was very vague because it only stated that the class A chimney coming through the wall and into the room must protrude 3" minimum.  It seemed to me like this was to give proper clearnace for the transition from the class A to the double wall stove pipe, but wasn't sure how to handle the air shield being within that 3" minimum.  

Thank you!


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## akbear (Oct 7, 2013)

Vague is the keyword, if you look at three different selkirk instruction manuals you often get three different distance recommendations as well in that off chance they have clearly spelled something out.  For some reason or other they can't seem to co-ordinate the manuals or just don't care to update them when they've set out a new standard.

One thing you might want to consider (mostly unrelated to the actual question) is putting up a radiant barrier over the studs before building out.  I did that in my wall reconstruction and I was really pleased with the performance of that wall over the past winter before the stove was installed.  In my case I used a class A blanket (the type like garage door blankets are made of, two layers of heavy foil sandwiching some sort of bubble wrap material) over the studs as a back to the air gap.

I did also place a ring of the same rockwool type insulation that can go inside the thimble as well as in the corners around the thimble in the airgap surrounding the thimble as going through a winter with only a plastic grocery bag stuffed with insulation scraps I didn't want the metal thimble to be a conduit to bringing the cold into the wall to chill my interior walls or as a place for condensation to collect and drip into my wall (I have a canadian envelope, so basically I have an airgap all the way around).  And that was the second thing that exceeded my expectations, I didn't have a drop of condensation on that trim ring all winter long.


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## bag of hammers (Oct 8, 2013)

Johnny G82 said:


> It will have a 1" air space spaced out with strips of durock and vented top and bottom, with Durock attached to the strips.



On my old stove with similar heat shielding set up - I picked up a couple lengths of metal furring strips - perfect air gap (I ran them vertical and a up couple inches from the floor) - no need to cut thin strips of durock, etc.  Just something to consider...


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## Backwoods Savage (Oct 8, 2013)

Johnny G82 said:


> Hi,
> 
> I am installing a Hearthstone Phoenix that* will be vented out through an exterior wall (I realize that this is not ideal) and then up about 15' through a class A *chimney.  My question is, which type of class A chimney will perform best in terms of draft and creosote build up on the exterior?  Double or Triple wall?
> 
> ...



Welcome to the forum Johnny. 

You state that it is not ideal going through the exterior wall then up. In that case, me and many others have a bad setup! There is nothing wrong with doing this but you must know that the horizontal section must have a minimum of 1/4" rise per foot of horizontal. We went 1/2" or more per foot and have no problems. Our chimney is also short and should not work, but it does the task just fine.


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## Johnny G82 (Oct 8, 2013)

Hi Dennis,

I didn't mean to make the exterior chimney setup sound bad, only that everything I had read about it seemed to indicate that it was less ideal than going straight up inside .  I'm glad to hear it works well for you!


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## Obadiah (Oct 10, 2013)

As a firefighter, I would encourage anyone looking to do an exterior Class A chimney installation to first make sure they go with a chimney that meets Canadian specs as the pipe is better insulated, some is even 2" thick. The new DuraVent DuraPlus HTC meet these specs and is vast improvement over DuraPlus which I wont sell to anyone north of Florida. Next go to the NFPA website, (National Fire Prevention Association) website and see if you can find the National Statistics for home fires related to chimneys. I don't have that info in-front of me and were swamped so I don't have time right now to look it up, maybe latter. Saw the data a year or so ago and was amazed at how many home fires we caused by wall thimbles verses straight up through the roof. They attributed it to the fact that the creosote builds in the horizontal pipe in the wall and the fact that the smoke has to do a 180 degree turn before it goes up the chimney which is cold when you first fire the stove and will condensate as it heats up creating creosote issues. When a chimney fire does start, the risk of the elbow inside of the home melting increases with every minute the chimney is burning, once it burns through you literately have a rocket engine inside your home burning from both ends at over 2000 degrees!! A sure fire way to burn a house down before the local fire dept can respond. I will no longer do any through the wall installations or those types of chimney sales unless there is no other way to do the job, then I spend a great deal of time with the customer teaching them how to properly clean their own chimney, if they wont clean their own chimney, I'll pass on the sale. The worst thing that generally will happen to a through the ceiling type of installation during a chimney fire is the chimney cap melts and falls off and rolls off the roof starting a fire in the shrubs on the outside of the house, a far better option if your have to have a chimney fire in my opinion. This is because there is not restriction in the pipe and the flames, sparks and heat take the path of least resistance and blow out the top of the chimney stack, the pipe does not get as near as hot as one with elbows which trap the heat. Most folks would rather go through the wall because they are afraid of a rood leak around the flashing. In thousands of installations i have done in my career I have never had a call back for that problem. A properly install roof flashing will not leak, even installed in a metal roof with heavy snow loads. Being in the Hearth business over 33 yrs. now looking back I can safely say that 90% of the folks that call me with smoking and drafting issues had some form of an exterior installation. I just had a customer called with questions so I did a quick search and as usual my friends here at Hearth.com were already on it here on this tread, so I thought I'd drop in add my two cents and say hi! Thanks for all you guys do to help folks get a safe install, the firefighters of the world applaud you!
Blessings!


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## johnstra (Oct 10, 2013)

Woody - I sent you a pm.


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## bag of hammers (Oct 10, 2013)

Obadiah said:


> A properly install roof flashing will not leak, even installed in a metal roof with heavy snow loads.



+1

Of 2 installs at my place - the 1st (a DIY - me, @ 14 years ago) never had any leaks - bullet proof - the 2nd install ("pro" roofers) leaked by year # 3.  It looked pretty, but a sanity check with a few experienced roofers on how to fix it led me to know how they screwed it up to begin with.  

Kudos to you for doing quality work on peoples' houses (and the firefighter work you guys do).


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## Johnny G82 (Oct 10, 2013)

Obadiah, I appreciate your caution about being fire safe and cleaning the chimney regularly, but are you saying that you wouldn't trust a properly installed class a chimney through the wall installation with the standard Duravent Duraplus system?

I have to admit, your post is making me nervous about my plan to use a through the wall exterior chimney installation with this product


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## Obadiah (Oct 11, 2013)

Johnny G82 said:


> Obadiah, I appreciate your caution about being fire safe and cleaning the chimney regularly, but are you saying that you wouldn't trust a properly installed class a chimney through the wall installation with the standard Duravent Duraplus system?
> 
> I have to admit, your post is making me nervous about my plan to use a through the wall exterior chimney installation with this product



Johnny,
I'm sorry about making you nervous, but yes, I would never do a through the wall install unless there is no other way, then I would definitely choose a different pipe if the installation was anyplace that can see a 30 degree or lower temperature. DuraPlus is an outdated triple wall air cooled, poorly insulated chimney that only carries a UL 103 rating and has been regulated to the BIG BOX STORES and is not sold by any chimney pros I know in the North Country. We were given DuraTech by DuraVent as our Pro Grade Chimney, which carries a  UL 103 HT and ULC S604.rating and is only supposed to be sold by authorized dealers and installed professionally. This may be replaced again and the box stores will receive the DuraTech as the DuraPlus is getting a bit long in the tooth even for those stores which are switching to the more modern Super Pro Pipe and Metalbestos pipe, which is a low grade Solid Pac Class A Chimney but better than DuraPlus in my opinion. Selkirk does offer a higher grade professional pipe for their chimney pros. My best guess is that we'll get upgraded to a better grade of pipe so DuraVent can remain competitive in the Big Box game and we'll get DuraPlus HTC which is tested to Canada's stringent 2100 degree F standard, ULC S629. and DuraTech Canadian which carries a  ULC S629, ULC S604 and ULC S610 rating which is superior to anything else that DuraVent offers. By the way DuraVent has been purchased again and is now owned by M & G Group headquartered in the Netherlands. The good news is they also purchased Security Chimney which is excellent Canadian pipe and I'm sure that will be great for DuraVent. In fact the new DuraTech Canadian pipe shares many similarities to Secure Temp by Security. I personally prefer to use only chimney that meets the tougher Canadian specs in my own installations as were in Montana where we can see 50 below. My favorite is Security GX which is only available in 7". We sell a lot of pipe because we offer complete chimney design services and tech support and competitive pricing with the Hearth Appliances we offer as a package deal. One Stop Shopping with excellent support and service before, during and after the sale. With so many folks in the chimney pipe game now, like Lowes and Home Depot and some online companies that are selling chimney pipe for less than guys like us can buy it for, this is the only way we can remain competitive. There are still enough pros left out there that the chimney manufactures know they have to help us out somehow or we'll all be put out of business. The guys that really care about safety and buying the best pipe will continue to buy from companies like Obadiah's and the rest will run to Lowes and HD and continue to call us for advice and parts that the box stores don't offer to complete their installations. When will folk understand that the big guys are killing the little guys and when were all gone the Big Guys will raise the prices and you wont get any service from anyone and pay through the nose for everything? Fortunately the Big Guys have stayed out of stoves as they have gotten their butts sued off for unbelievable incompetency  but they are getting brave again and the suppliers are getting greedy. Hope this helps answer your questions, perhaps someone else can take the time to break down what all the UL listings actually mean in terms of burn rates and testing times, once folks understand that, it all becomes very clear what I am saying and how much better the Canadian pipe is verses our stuff. I still have a bunch of quotes to do for folks yet tonight. Blessings!
Here are your references http://duravent.com/ProductCategory.aspx?c=8
http://www.m-ggroup.com/
http://www.m-ggroup.com/the-companies/
http://ulstandardsinfonet.ul.com/scopes/
http://www.nfpa.org/
http://www.ul.com/global/eng/pages/


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## oldspark (Oct 11, 2013)

Since dura plus has insulation and an air gap I was under the inpression it was a good product, you are saying it is not, much better then the triple wall with no insulation for sure
I edited my post a little, I guess there is more then one duraplus products.
Duraplus triple wall-UL Listed to UL 103HT (MH7399).
Sure as hell dont want to promote a product that is not as good as the double wall insulated.
I agree with through the wall not as good a way to do it but as BWS states done right it should be fine but Obadiah's advice is not to be taken litely.


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## Backwoods Savage (Oct 11, 2013)

Johnny G82 said:


> Obadiah, I appreciate your caution about being fire safe and cleaning the chimney regularly, but are you saying that you wouldn't trust a properly installed class a chimney through the wall installation with the standard Duravent Duraplus system?
> 
> I have to admit, your post is making me nervous about my plan to use a through the wall exterior chimney installation with this product



Johnny, Obadiah has some good ideas and probably more experience than I. However, I will say that I've known several folks with through-the-wall installations and none have had a problem if it was installed correctly. We have had a through-the-wall setup for about 34 years and have never had a problem. But I can see where some could have a problem especially if they insist in burning in the old ways and not drying their wood properly. That is the cause of creosote and creosote is an accident waiting to happen. We burn wood that has been in the stack 3 years or more so we simply do not get any creosote in our chimney. I'll add that our chimney has not seen a brush for 4 years now and it does not need one either. Another point is to have the horizontal section have some rise to it. Code calls for 1/4" rise per foot of horizontal. We went 1/2" or more. Result? No problems. 

I have seen some very poor setups. That is, some with nor rise in the horizontal and some with an actual decrease! Bad for sure.


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## Obadiah (Oct 14, 2013)

If you have to go through a wall in a Northern Climate and there is no other way to do it, you should enclose the pipe in an insulated chase to keep it as warm as possible. Here are some picture that of our customers chimney installations that I think represents a good way to do this type of install.


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## knowledgeseeker (Dec 28, 2013)

Hi there, I've never posted anything before but here goes. I am preparing to have installed a new Monessen/Majestic Biltmore SB44HB woodburning fireplace and have been trying to educate myself on the whole process.  As per manufacturer requirements, the chimney system components used for installation must be those tested/made for this c / UL /  us listed unit – specifically CF11 chimney piping in this case, which were ordered at the same time with the unit.  I did not realize initially that the piping did not come with mineral insulation between its layers (nor is it stainless steel I think), and so have been researching double wall piping to address my concerns.  From what I understand, the CF11 appears to be double wall air cooled piping - however  there is also a 2” clearance installation requirement for the chimney ... does this make it air insulated chimney piping? 

Also, I live in a northern/cold climate and am trying to ensure install is done with optimal conditions with all safety precautions being observed of course.  As such :

a) the fp unit, chimney/chase is located on exterior wall but within the heated building enveloppe on the main floor of the house
b) surrounding exterior walls have been insulated as per manufacturer recommendations/ with Roxul mineral wool insulation
c) sufficient and proper chimney height and rise are confirmed
d) chimney trajectory not perfectly straight but goes as straight up as possible with only one small offset/30 degree bend so as to maximise draft
e) cold climate kit will be installed as well as combustion air kit
f) attic insulation shield and firestops at all floor/ceiling levels

*Questions:*

1) _Can anyone confirm that the CF11 piping is indeed air insulated piping?

2) If not, or perhaps in any event, is there anything further to be done to increase insulation while it is still possible/space is accessible or to reduce chances of any condensation or corrosion of the piping over the long term? (is it permitted or advisable and is there any benefit to adding a ceramic insulating blanket to the outside of this venting within the chimney chase?)_

3) _As this is a new construction, should I try to incorporate a small access door on one of the interior house walls of the chase on the second level (top floor) to permit access and visual examination of the inside of the chase/exterior of the chimney for the future or is this really unecessary?_

All recommendations are welcome. Thanks in advance.


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## Obadiah (Dec 29, 2013)

> *Questions:*
> 
> 1) _Can anyone confirm that the CF11 piping is indeed air insulated piping?
> 
> ...


Greetings Knowledge Seeker, you have come to the right place for all things Hearth related.
1. Unfortunately what you have there is Air-cooled Chimney and it is tested to a lesser standard of Class A. 
2.There is nothing you can or should do to change the way the pipe is designed to function. If you do you run the risk of causing a fire.
3.I always put an access panel in every chase I build as I am also a professional firefighter and do insurance investigations on the side after the home has caught fire because of the fireplace installation. You would not believe how many air cooled chimneys I have seen come apart with builder box fireplaces. There are installers out there during the building boom of a few years ago that would brag that they could install 4-5 of those fireplaces in a day! Of course quality was not the focus. If your installing it yourself you will be more careful snapping the chimney together. Being able to inspect any chimney up close and personal is a great idea, my clients would have me service their fireplaces every year and I would clime into the chase and clime up from fire-stop to fire-stop where I would install a trap door to inspect each seam to make sure there was no black spots, or separations. Many times a chimney will come apart later if not properly connected at the seams when the chimney sweep shows up to clean the chimney. Some don't seem to enjoy their jobs and can get pretty violent up there ramming the chimney brush up and down especially if there are any offsets in the chimney system. They can and do come apart if they are not properly supported. 

You have what is known in the business as a "Builders Box" and the fireplace will suck more heat out of your home than it will put in. You mentioned your in a cold climate, if your expecting this fireplace to reduce your heating bill it will actually do the opposite. http://www.woodstoves.net/majestic/wood/biltmore-44-sb-fireplace.htm It is designed to burn hot and fast and is not subject to the same EPA our UL regulations as heat producing fireplaces because you'll get tired of feeding it wood before you would every try to use it to heat with, you cant turn it down low enough for an all night burn, so it is just for decoration, that is it. The chimney is Air Cooled because the stove burns hot and fast and does not make much creosote or smoke, unlike a fireplace that you can shut down for an all night burn like a http://www.woodstoves.net/osburn/wood/stratford.htm which in my humble opinion is one of the best fireplaces on the market for the price. You can use a wide verity of insulated Class A Chimney with the Stratford. It is made by SBI in Quebec, The Osburn Stratford  has a lifetime warranty and produces 75,000 BTUs of usable heat without a blower because of its convection design. It will heat up to 2000 Sq. Ft and takes a 21" log.

My personal favorite wood burning fireplace for Northern climates is the BIS Tradition also made in Canada in Quebec, well until Lennox bought them which is a very unfortunate thing, in my opinion. I have been selling and installing BIS fireplaces for almost 20 yrs now and they were the best fireplace made for heating. Built very well with high quality steel they can be burned with the doors open for the ambiance and snap crackle pop, or closed for heating efficiently with wood. As with all Hearth appliances the chimney system is the engine that drives the appliance just like the engine drives the vehicle. You would never put a Yugo engine in a Beamer nor should anyone install an air cooled chimney on a high quality fireplace. There are several high end fireplaces that only come with air cooled chimney, which is a total joke in a cold climate, like Ontario where you live or Montana where I live. I will not sell a high end fireplace that is used for heating North of the Mason Dixon Line. What happens is when you turn the fireplace down at night for a long overnight burn the fireplace does not burn as hot, an air cooled chimney can cool down to the point that it will quit drafting. If someone turns on a bathroom fan, or worse yet a home with more than one that is well constructed and tight, negative pressure will build in the house pulling air down the chimney and you'll wake up to a home full of smoke, pretty scary if you don't realize what is going on. I have seen that scenario happen before and hear horror stories from folks who call me later and say, "Woody you were right I should have listened to you, that $1000 dollars I saved on the fireplace just cost $20K in smoke damage and my wife is not a happy camper." 

The BIS Tradition is available with 7" Security GX chimney which is 2" thick solid pack pipe that is designed for the BIS Tradition and Canadian Arctic winters. This chimney will burn hotter and draft better than any chimney out there, minus the new M&G DuraPlus HTC which is also 2" thick. There are some other chimneys out there that are 2" thick that are great for cold climates like the Yaak where I live, we can see 50 below. When it gets that cold you have no idea what it is like, steel breaks like glass from being brittle. There are many really cool features with the BIS Tradition, like the Turbo Boost feature which allows you to set the fireplace air control in the morning when you stoke your fire and walk away. It is like leaving the door cracked open for a half hour while the fire reestablishes itself after you reload the firebox with wood. It will automatically over the next couple hours gradually shut itself down to whatever setting you set the fireplace at, low, medium or high burn. No more leaving the door cracked in the morning while you drink a cup of coffee waiting for the fire to get going, only to get a phone call and space the fact the door is open. Off to work you go, up in smoke the wood goes and you come home to a cold house because you forgot to shut the door. Oppps.....

80,000 conservatively rated BTUs and a 30" log make things really nice for cutting your wood, she will keep you and your family warm and cozy in the most extreme climates, the BIS Tradition is my choice in wood fireplaces in cold climates. http://www.woodstoves.net/security/bistradition.htm 
She even comes in a Compact Edition and is called the BIS Tradition CE she is rated at a conservative 55,000 BTUs and will heat up to 1500 sq. ft. burning 20" logs. She uses 6" Security ASHT chimney which is also great pipe, but not 2" thick.
http://www.woodstoves.net/security/bistraditionce.htm

Well I hope I have educated you on fireplaces and the chimney systems that make them what they are. Bottom-line Air Cooled chimney works ok for fireplaces that burn quick and hot, not so much for those that claim to be efficient and get a long burn time, maybe down South they work OK, where you and I live, not so much. I would advise staying clear of them and any dealer that does not know the difference.

Have a Blessed and Prosperous New Year 2014!


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## knowledgeseeker (Jan 3, 2014)

Thank you so much for taking the time to write a thorough and informative response. Your recommendations are much appreciated.  I am disappointed to find out that the quality of the chimney piping purchased is not grade A.  This confirmed my initial worry (which prompted me to write here) as I saw when it was delivered to the site that it was not insulated like what I had seen before. I wrongly assumed that a more expensive fp model would be paired up with same in piping. However, luckily, the fireplace will not be a main source of heating for the house. It was supposed to be for a back-up heat source in case of a power outage/emergency (although it now appears that I should perhaps not use it in this situation if it will suck out more heat from the house that it can provide!?) and for pleasure. Fortunately, I will have the benefit of a highly efficient water radiant system for the whole house which will permit me to use this fireplace merely for pleasure I suppose - for "hot and fast" burns as you call it and for a decorative purpose.  My family and I love  the crackle (and subtle smell) of a wood burning fireplace and the family activities which surround it.

That said, safety is paramount. Following what you said:

1- a) are there any special recommendations on installation to ensure that the snapping together of the chimney sections/seal created are as tight and sturdy as possible? I did duly note your comment to provide proper support to the components with special attention to any offsets and avoiding cantankerous chimney sweepers!

b) Any specific spacing recommendations for providing support to the chimney sections above and beyond manufacturer's recommendations? 

I will ensure to plan for as many access doors as possible to enable visual inspection of the chimney components.
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This said, I  must admit I am now concerned about the possibility of smoke being sucked back accidently into the house. Could you please help me further understand  how to avoid this:

As a newly constructed house, the envelope will be tight.

2- a) Will making sure the fire is out in the fireplace before bed (therefore never leaving it alight/alive at night and unattended) ensure that one does not provoke the chimney to cool down to a point where it stops drafting or are there other situations where this can happen (negative pressure in the house?) ?

b) Should I ensure that no fans ever run at the same time as the fp?

I will have an HRV and a dedicated venting system in the bathrooms but have no experience with this yet and am therefore still unclear on the potential impact of its functions on venting and possible "backdrafting"(if that is the correct term). In an ideal world, I would be able to use my kitchen fan  which will have about 650CFM, at the same time as the nearby fp, without worrying about "backdraft" ruining the house with smoke! (and also my bath fans for that matter!)

c) should I therefore do a blower test or any other test once all the hvac systems are up and running to ensure that no smoke gets sucked back into the house/ have proper pressure in the house (although I don't know what that would be! non negative pressure?) and am I confusing 2 concepts here?   

 - - - - - - - - - - - - - - -  - - - - - - - - - -
3) Apart from an annual visual inspection of the chimney connections to ensure there are no black spots or separations, if the type of use and burning I will get from my fp is hot and fast therefore resulting in little creation of creosote or smoke, coupled with moderate use during the winter, how often should chimney cleaning be done specially if cleaning (albeit aggressive cleaning) can contribute to loosening the seals between components? 

Thanks again for your expert advice on these issues.  It is much appreciated.  Best wishes for the New Year as well!


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## Obadiah (Jan 26, 2014)

> [
> 1- a) are there any special recommendations on installation to ensure that the snapping together of the chimney sections/seal created are as tight and sturdy as possible? I did duly note your comment to provide proper support to the components with special attention to any offsets and avoiding cantankerous chimney sweepers!
> *Depending on the brand of Class A Pipe, when you put it together it will assemble differently, Air Cooled chimney snaps together and is pretty much impossible to get apart once assembled properly. Other Class A Solid Pack Pipe twist locks together and can be unlocked and taken apart by simply unscrewing like a lid on a jar, a couple screws will prevent it from coming unscrewed.*
> b) Any specific spacing recommendations for providing support to the chimney sections above and beyond manufacturer's recommendations?
> ...


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## Obadiah (Feb 19, 2016)

knowledgeseeker said:


> Thank you so much for taking the time to write a thorough and informative response. Your recommendations are much appreciated.  I am disappointed to find out that the quality of the chimney piping purchased is not grade A.  This confirmed my initial worry (which prompted me to write here) as I saw when it was delivered to the site that it was not insulated like what I had seen before. I wrongly assumed that a more expensive fp model would be paired up with same in piping. However, luckily, the fireplace will not be a main source of heating for the house. It was supposed to be for a back-up heat source in case of a power outage/emergency (although it now appears that I should perhaps not use it in this situation if it will suck out more heat from the house that it can provide!?) and for pleasure. Fortunately, I will have the benefit of a highly efficient water radiant system for the whole house which will permit me to use this fireplace merely for pleasure I suppose - for "hot and fast" burns as you call it and for a decorative purpose.  My family and I love  the crackle (and subtle smell) of a wood burning fireplace and the family activities which surround it.
> 
> That said, safety is paramount. Following what you said:
> 
> ...



Sorry for the delay, for some reason the first reply never posted properly.
Here are the answers to your questions.
1- a) are there any special recommendations on installation to ensure that the snapping together of the chimney sections/seal created are as tight and sturdy as possible? I did duly note your comment to provide proper support to the components with special attention to any offsets and avoiding cantankerous chimney sweepers!
b) Any specific spacing recommendations for providing support to the chimney sections above and beyond manufacturer's recommendations?
*Depends on the brand of chimney, some require additional screws installed to meet UL, so I can not give an answer other than the pipe must be fully engaged male end down, female end up, so the creosote will run down inside the joints and not on the outside of the chimney pipe. If the seams are dripping creosote then the pipe is installed upside down! Unbelievable how many times this is the case....Offsets are where the issues generally also arise, so even though the joints are properly joined and secured, the weight of the pipe above will cause the joints to open up over time, if not properly supported. Add a angry chimney sweep and something will come apart eventually......so make sure each offset is properly supported with the elbow straps the pipe manufacture offers, or even plumbers tape if your on a job where there are no supports. Always go overboard on supporting offsets against gravity pulling down on the chimney installed above the offset, as well as laterally so the chimney does not move around which causes stress to each joint. This is how they come lose 20 yrs later, the screws work out first and then the chimney will begin to unspin itself as it is slopping around inside the chase. By code there needs to be a firestop at each floor level inside the chase so the chase itself does not act like a chimney in the event of a fire starting inside the chase, or burning through into the chase.  These firestops also act as stabilizers and places to attach support brackets and such, which lock the pipe in place and prevent the pipe from moving or spinning lose. *
2- a) Will making sure the fire is out in the fireplace before bed (therefore never leaving it alight/alive at night and unattended) ensure that one does not provoke the chimney to cool down to a point where it stops drafting or are there other situations where this can happen (negative pressure in the house?) ?
*It will definitely help not to have a potential issue by making sure the fire is almost out when you turn in for the night. You'll have an outside air kit on your fireplace which will suck combustion air in from a 3 or 4" aluminum flex tube connected to a inlet on the outside of the chimney chase that will feed the fireplace fresh air as long as it is open and air can flow. Unfortunately when the cold air comes into this tube it builds condensation. If the tube is dipped down it will collect water and begin to sag and act like a drain trap, either restricting or blocking off the air flow as the water continues to collect. If the fireplace is not being used over the summer, the water evaporates and everything works great. Took a long time to get that one figured out. Anyhow make the loop go up not down so it wont trap water.*


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