Another wood stove install into an existing brick fireplace

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

jawsont

Member
Dec 18, 2012
33
1950's cabin in the woods - the fireplace was covered over 30 years ago and in the space in front there was a wood stove installed. The exhaust pipe threaded through a steel plate covering the opening to the fireplace and exhausted into the chimney.

I finally convinced my father to get rid of the old stove, get something more efficient and exhaust directly up the chimney via. a stovepipe. In addition, the masonry around the fireplace (what do you call that area? the hearth is the floor, the mantle is above, but it's the bricks surrounding the fireplace) holding the clay bricks is badly crumbling - to the point where the bricks we removed we simply had to lift out with virtually no force required. We removed the old steel fireplace (see below) insert and I now have questions.
[Hearth.com] Another wood stove install into an existing brick fireplace


Two questions specifically:

1) The plan was to install the wood stove (a Pacific Energy True North) into a re-built hearth (we have to extend the hearth out to meet the 18" rule here in Canada, but that's easy enough to do). As you can see the opening is about 20 inches across in the back, 30 inches across in the front. Once we line the whole area with concrete backer-board and face it with tile (cosmetics more than for combustive reasons - though it helps with that too I guess) we are left with FAR less than the 16 inch clearance PER SIDE that Pacific Energy requires for the install. I think we get about 4" of clearance to the back of the existing fireplace (where you see the red brick), we'll have about 2" of clearance per side at the back of the stove and closer to 5 inches of clearance per side towards the middle when the wood stove juts out past the existing fireplace. My question is this - Pacific Energy requires 16 inches to each side and 6" to the back, are we ok with only a few inches of clearance since the existing sides are 1.5' of firebrick? I think from other threads I've read that I'll be ok, but the last thing I want to do is make a stupid mistake for lack of research. Better to have confirmation :-)

2) The chimney above lintel is cracked and has loose bricks for about 5 courses (from the angle iron to about 1/2 up the wall). The pink crappy masonry they used is all but dust (a fingernail causes it to slough off). It's why we removed the mantle area around the existing fireplace. The farther you get from the fireplace, the stronger the masonry is. Thankfully the pink crap was used only in the section of chimney visible in the room. Where the chimney passes through the ceiling, and on the back side of the fireplace, they used a much harder masonry that might even be regular concrete for the remainder of the chimney (it's white and there doesn't appear to be any sand in it or if there is, it's small or hidden). Are we ok to do a standard repointing of all the compromised mortar, then support the chimney with another piece of angle iron? Our idea was to 1) repoint the chimney where the pink death is and 2) keep the existing angle iron that carries the back side of the brick, then position another piece of angle iron mirroring it (think of two L's facing each other) on the front carrying the front side of the brick. Does that make sense? Would that work?
 
Last edited:
My main concern would be that sagging lintel and what's causing it. There's probably a lot of weight pressing down on that angle to make it sag. I'm no expert, but it seems to me that it would take a lot more than repointing to fix what you have there. Is there a clay tile inside the chimney?
What would be the purpose of the second piece of angle?
 
I *think* that the settling of the structure maybe caused the lintel to bend (we're talking about about a 1/8 to 1/4 inch deformation in the steel in the middle). There's no cracking of the mortar anywhere else along the chimney except right above the lintel for a couple of courses, so it might even be that the lintel sagged as the original guy built the place and it's been deformed ever since. Or maybe, as the mortar gave way those bricks nearest to the lintel "fell loose". Don't get me wrong, I'm a bit concerned about it myself. I'm not sure it would be possible to support the bricks higher up and remove the front bricks and rebuild only that portion of chimney.

The only reason I was considering the 2nd piece of angle iron was because at present, the bottom most course of bricks in the front portion of the chimney is supported only to the depth of the steel (about 1.5"). That leaves the lion's share of the brick unsupported (whereas before we took out the fireplace steel liner the front of the brick was being supported on a thin pad of masonry on top of the liner. Right now - there are a couple of bricks right in the middle resting on the lintel that are "tipped forward" (as in the mortar no longer binds them to the brick above).

[Hearth.com] Another wood stove install into an existing brick fireplace
 
Was this really a working fireplace at one time? The proximity of wood all around it concerns me. Given its sad shape, what about just bricking it up and tapping into the chimney above the damper area?
 
Hehe, I guess it does look pretty horrible in that picture. Once we saw the extent to which the mortar along the bottom was crumbling we removed all the facing brick. In this shot we hadn't removed the debris, nor removed all the old insulation around the old steel insert. The fire-brick along the sides isn't pretty (but was originally hidden). That said, it does form a nice surface on which we'll apply backerboard. After that our plan is to overlay it with river-stone. Believe it or not it was once a pretty brick fireplace.

W.r.t. question 1 I had - am I right in interpreting from other threads that since the old fireplace is all brick the need for the stove clearances isn't really required?
 
The clearances in the manual assume a legal and proper masonry fireplace. What is showing here does not seem to fit that qualification. That said, just follow the stove requirements, including paying attention to the surrounding wood paneling for clearances.
 
Quick follow-up question. We are venting our stove with supervent double-walled pipe up the brick chimney. Ideally we'd have gone stainless insulated up the chimney, but there aren't the clearances (the interior of the brick chimney is only 11" x 7.5". Long and short - we're using double-walled pipe. We want to cap off the chimney with a stainless cap to prevent bugs/moisture from coming back down the chimney and have the stovepipe extend past that.

Question is - what can I have protruding out of the top past our chimney cap? Surely not double-wall since everything I seem to read suggests insulated stainless. If so, I don't need the major thimbles that I seem to find everywhere for insulated pipe do I? Ideally we'd find an adaptor to connect the double-wall to the short (1-2') stainless throw past the chimney-cap. Definitely stuck since most of the stove stores around here say you can't marry double-wall with stainless insulated, but I feel like they're full of BS since that's what I have at my house (which passed WETT), and by buddy has the same thing at his first-second floor transition.

Help please?
 
Specifically what brand and part number double-wall pipe are you considering using that would fit up a 7.5" wide flue? Make sure it is not gas stove pipe. maybe you just are using the wrong term to describe it. You should be using an insulated 6" stainless liner or a preinsulated liner like DuraLiner.
 
We have Selkirk double walled telescoping pipe. Used to be branded superpipe i think. This is the pipe, though we got ours from home hardware.

http://www.truhardware.ca/cms/app/en/products/productDetails.html?pid=150341

Specifically what brand and part number double-wall pipe are you considering using that would fit up a 7.5" wide flue? Make sure it is not gas stove pipe. maybe you just are using the wrong term to describe it. You should be using an insulated 6" stainless liner or a preinsulated liner like DuraLiner.
 
That is not chimney pipe and is definitely not safe to use in this application.
 
I may be thick, but why not? It's CSA stamped pipe for wood stoves. or are you differentiating between stove pipe and chimney pipe?
 
Yes.
 
Connector pipe and chimney pipe are two different things. That is connector pipe. From the stove to the chimney.
 
Status
Not open for further replies.