Can a masonry chimney be ‘lined’ with insulated double wall pipe?

[FixerUpper]

Greetings from Saskatchewan, Canada.
Before I get to the topic I must mention how grateful I am that the Google led me to this forum. My wife and I have been scouring the forums and have found answers to so many questions. Thank you for all the amazing vault of information.

We recently wrestled a Drolet Escape 1800 down the stairs of a 1950s built single-story farmhouse where we plan to reside post-retirement. A lot of renovation needs to be done to make this building comfortable and code-compliant. The house has an existing masonry chimney that has served past wood stoves and an oil burning furnace. The chimney is currently unused because the primary heat is now a propane direct vented furnace. Our plan is to eventually have the wood stove in the living room on the main floor. I say ‘eventually’ because before that happens there’s a LOT of renovation work required before it can be installed there.

So, the plan was to line the existing masonry chimney and use the Drolet in the basement as a supplemental heat source for a few years . After that we’d place it up on the main floor where it belongs and have an interior double-wall insulated stainless steel chimney go straight up about 16’. The masonry chimney from the basement would quite likely be capped off as we have no plans to finish the basement. Then my wife asked an interesting question (I hate it when she does that): “Why can’t we just buy the stainless steel double-walled and insulated pipe and use it as the masonry chimney ’liner’ for now and then when the renovations are done, pull it out and use it on the main floor?” If this can be done it certainly would save the cost of an insulated liner that would go unused. After looking at the Selkirk Supervent specs it looks like it would fit. The masonry chimney is 17” square with a 9.5” square opening and the Supervent is just over 8” in diameter. The old (perfectly straight) masonry chimney would basically act as a chase I guess. Can this be done and still comply to building codes?

I appreciate all feedback from anyone patient enough to read to the end this long, rambling post.

-Cheers

 

[bholler]

Greetings from Saskatchewan, Canada.
Before I get to the topic I must mention how grateful I am that the Google led me to this forum. My wife and I have been scouring the forums and have found answers to so many questions. Thank you for all the amazing vault of information.

We recently wrestled a Drolet Escape 1800 down the stairs of a 1950s built single-story farmhouse where we plan to reside post-retirement. A lot of renovation needs to be done to make this building comfortable and code-compliant. The house has an existing masonry chimney that has served past wood stoves and an oil burning furnace. The chimney is currently unused because the primary heat is now a propane direct vented furnace. Our plan is to eventually have the wood stove in the living room on the main floor. I say ‘eventually’ because before that happens there’s a LOT of renovation work required before it can be installed there.

So, the plan was to line the existing masonry chimney and use the Drolet in the basement as a supplemental heat source for a few years . After that we’d place it up on the main floor where it belongs and have an interior double-wall insulated stainless steel chimney go straight up about 16’. The masonry chimney from the basement would quite likely be capped off as we have no plans to finish the basement. Then my wife asked an interesting question (I hate it when she does that): “Why can’t we just buy the stainless steel double-walled and insulated pipe and use it as the masonry chimney ’liner’ for now and then when the renovations are done, pull it out and use it on the main floor?” If this can be done it certainly would save the cost of an insulated liner that would go unused. After looking at the Selkirk Supervent specs it looks like it would fit. The masonry chimney is 17” square with a 9.5” square opening and the Supervent is just over 8” in diameter. The old (perfectly straight) masonry chimney would basically act as a chase I guess. Can this be done and still comply to building codes?

I appreciate all feedback from anyone patient enough to read to the end this long, rambling post.

-Cheers

It would be possible if chimney pipe would fit. But that is unlikely

 

[FixerUpper]

It would be possible if chimney pipe would fit. But that is unlikely

Thanks bholler.
You’re right. I checked the manufacturer‘s installation sheet and it looks like the diameter is just over 10”. That makes me wonder if we can even accommodate a conventional insulated ss liner?

If I’m reading the codes correctly masonry chimneys need a 2” clearance to all combustibles including framing, drywall etc. I dug out some mortar and cobwebs to look up the sides of the chimney. Initially it was encouraging to see the framing 2” away and the flashlight shows what looks like a clear path almost to the roof. But on 1 of the other 2 sides it’s only 1” away and then it looks like a framing stud was placed right up against it running vertically as far as my light carries. Probably from a closet renovation decades ago.

From reading previous posts it sounds like an uninsulated ss liner inside isn‘t code compliant even if the chimney is otherwise sound.

Bummer

 

[bholler]

Thanks bholler.
You’re right. I checked the manufacturer‘s installation sheet and it looks like the diameter is just over 10”. That makes me wonder if we can even accommodate a conventional insulated ss liner?

If I’m reading the codes correctly masonry chimneys need a 2” clearance to all combustibles including framing, drywall etc. I dug out some mortar and cobwebs to look up the sides of the chimney. Initially it was encouraging to see the framing 2” away and the flashlight shows what looks like a clear path almost to the roof. But on 1 of the other 2 sides it’s only 1” away and then it looks like a framing stud was placed right up against it running vertically as far as my light carries. Probably from a closet renovation decades ago.

From reading previous posts it sounds like an uninsulated ss liner inside isn‘t code compliant even if the chimney is otherwise sound.

Bummer

Yes it needs to be insulated. Even if you had required clearances you want it insulated anyway. To fit an insulated liner you may need to remove the old clay liners.

 

[NickW]

I used Duravent insulated rigid liner, which has a 0" clearance to combustibles on the masonry chimney. The 6" oval fit inside my rectangular clay flue. This got me in code because I discovered in my research of the existing chimney that the house was not constructed with the 2" clearance where it passed through the floor & ceiling.

 

[Highbeam]

Thanks bholler.
You’re right. I checked the manufacturer‘s installation sheet and it looks like the diameter is just over 10”. That makes me wonder if we can even accommodate a conventional insulated ss liner?

If I’m reading the codes correctly masonry chimneys need a 2” clearance to all combustibles including framing, drywall etc. I dug out some mortar and cobwebs to look up the sides of the chimney. Initially it was encouraging to see the framing 2” away and the flashlight shows what looks like a clear path almost to the roof. But on 1 of the other 2 sides it’s only 1” away and then it looks like a framing stud was placed right up against it running vertically as far as my light carries. Probably from a closet renovation decades ago.

From reading previous posts it sounds like an uninsulated ss liner inside isn‘t code compliant even if the chimney is otherwise sound.

Bummer

The 10” OD stuff you found was triple wall air cooled. The 6” class a insulated double wall should be close to 8” OD.

 

[FixerUpper]

Thanks gents.
This obviously is going to require some more thought.

Looking at hardware stores websites or online chimney supply places liners are available but no liner insulation kits other than a total DIY. Even the sites we browsed last week for insulated chimney components are now out of a lot of stock. It looks like maybe the covid-19 situation is creating supply issues.

While I’m always game for going with the DIY approach, this is increasingly looking like the time to call in the pros. I did a search for WETT certified techs and it looks like the closest one is 5 hours away. Our location is somewhat remote but that’s still a little hard to believe.

 

[FixerUpper]

The 10” OD stuff you found was triple wall air cooled. The 6” class a insulated double wall should be close to 8” OD.

Thanks Highbeam

I hope it’s ok to post links.

http://www.supervent.ca/sitecore/content/global-configuration/selkirk/products/chimney/supervent-2100--jm

This is the 2” insulated pipe I was looking at. They did have a 1” insulated pipe which would have fit but the fine print in the install guide showed it as only meeting codes for wood stoves in the U.S. and only certain appliances in Canada.
Is it overkill to go to a 10” diameter insulated if an 8” would work? After it serves its purpose as a chimney liner (assuming that works) the pipe will be re-installed as a straight run inside a heated envelope for the first 6’ then about 5’ in an unheated attic then a final run of about 5’ outside above the roof. I was thinking that since this is a colder region (-15C this morning) that insulated would be better than just air cooled double or triple wall. Your thoughts on this would be most welcome.

-FixerUpper

 

[Highbeam]

Insulated is way better than air cooled. I’m an American duravent guy so I’m not familiar with the nuances of Selkirk and Canada. I would avoid anything 10” across though.

 

[FixerUpper]

Insulated is way better than air cooled. I’m an American duravent guy so I’m not familiar with the nuances of Selkirk and Canada. I would avoid anything 10” across though.

That’s good advice. Thanks Highbeam.
It looks like we can get DuraVent in Canada so I’ll look at that brand to see what they offer. Selkirk initially came up as a hit on an early web search so I just gravitated in that direction. I’ve got lots of time to research. There’s still 2 feet of snow on the roof. Global warming gave us a miss this year.

 

[DBoon]

The Selkirk Supervent 6" pipe is 8" outer diameter, insulated with mineral wool. I used it in inside a chimney in a house I am currently renovating.

 

[Nigel459]

There are a few lines of “Selkirk” chimney. In Canada the most commonly seen is the CF2100 line which is 10” OD. More insulation to meet the slightly stricter requirements for chimney fire temps, durations etc.

incidentally there’s nothing wrong with that 10” Selkirk product. It’s well built with good connections etc. I’ve used it a couple of times. Just looks a little chunkier. I do prefer the ICC stuff which is 8” OD and also good to go in Canada, but gotta get it from a dealer as far as I know.

 

[kennyp2339]

@FixerUpper I think one of the biggest over looked things when working with an existing reno is conforming to the existing layout. Since your doing the hard work and diving in elbows deep with elbow grease, ask your self if the existing chimney / layout of the final stove area is best for your long term, what I'm trying to say is sometimes having an existing chimney and rehabbing it doesn't make sense for long term heating, perhaps look at a different spot in the house on the main floor to place the stove and build a class a chimney to suite, might be easier and cheaper in the long term of things.

 

[FixerUpper]

@FixerUpper I think one of the biggest over looked things when working with an existing reno is conforming to the existing layout. Since your doing the hard work and diving in elbows deep with elbow grease, ask your self if the existing chimney / layout of the final stove area is best for your long term, what I'm trying to say is sometimes having an existing chimney and rehabbing it doesn't make sense for long term heating, perhaps look at a different spot in the house on the main floor to place the stove and build a class a chimney to suite, might be easier and cheaper in the long term of things.

Thanks kennyp.

Actually we do have a spot picked out on the main floor. For us, the basement location and chimney has always been thought of as a stopgap measure to heat the house until the renovations are far enough along for us to place the stove in a permanent location. As a liner the insulated chimney would be very close to the same length we would need for the permanent location. We were hoping to mitigate costs by potentially using the pipe for both purposes but it’s becoming apparent that it’s unlikely to work as intended.

The renos are almost a rebuild. My father and grandfather built the house with rough lumber sawed after logging the land in the early 50’s. My grandfather was a stone mason in the old country. The basement has thick stone walls built from the rocks he cleared from his field. We need to tackle everything from reinforcing and levelling floor joists, new subfloor and floor, new drywall, electrical, plumbing and probably an entire roof structure. Other than a new roof, I’ve already done this once with another 50’s built house so we know what we’re in for. A smarter man might just leave well enough alone and build a new house but I’d rather not give up on the old place. With these type of projects, the first casualty tends to be the budget from death by a thousand cuts. That’s one of the main reasons I was hoping to ’cheat’ (if possible) by reusing the insulated pipe.

Your advice and the guidance of others on this board has been extremely helpful. The initial though of heating with a wood stove was to reduce the 3-4K propane heating bill. As we do more research my wife has changed her concept of how the stove fits in with our plans. She’s gone from thinking it’s an ‘ok idea‘ as long is the stove can be unobtrusive and reside somewhere out of the way, to now embracing the concept of having it as a focal point of our living space. That opens up a lot more options for us. Thanks again for your insight.

 

[mcdougy]

Sounds like you have stone Mason in your DNA.....this wasn't super hard at the end of the day....

 

[FixerUpper]

View attachment 259642View attachment 259642
Sounds like you have stone Mason in your DNA.....this wasn't super hard at the end of the day....

That looks amazing.
So, if I’m reading correctly, if we do something like this we should start at the end of the day.
That‘s pure genius.

 

[blades]

Sometimes I believe that's where I started and it took weeks to get back to the begining. Is your place a 2 story? semi 2 story ( rooms on second floor kinda short heightwise like say about 6.5 ft (198 cm)? just curious because I have run into that.

 

[mcdougy]

The best part about it is....it heats 6200sqft entirely on its own (well ....I help out 3 to 4 times a day and CSS 5 cords or so.) Took about 7 days and a large amount of grinding the veneer stone to "square" them.....following the "Golden rule" of no X's . To me they are crosses. There is one there that snuck by me somehow.