Method for opening up brick fireplace to accomodate an insert

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molrobocop

New Member
Nov 4, 2015
6
Seattle, WA
Good morning/afternoon gents,

Background:

We have a conventional fireplace, and we're in the process of upgrading to an insert. This is the insert we're trying to get installed, and the associated requirements: http://ironstrike.us.com/products/montlake-230

Minimum Fireplace Width 25"
Minimum Fireplace Height 21-1/2"
Minimum Fireplace Depth 15-1/2"

This is a link to an online photo album with pictures of what I'm working with: https://imgur.com/a/R2dK1

rLxi2Ml.jpg

The existing dimensions are as follows:

To the top of the arch is 21.5"
The sides of the arch are 18"
Fireplace opening width is 40"
Fireplace back-wall depth is 27"
Fireplace depth is 21.5

Width and depth are good. Arch is a little too short to shoehorn the insert in as-is. One positive I believe I see is the bricks are unsupported on the backside.

zKP6HU1.jpg


So, what can we do here? Would the best approach be to cut a square notch out of the arch to give us clearance? I'm not super-concerned about butchering the brick. My logic is, to a different homebuyer, I doubt anyone would rip out a nice high-efficiency insert in favor of a wood-hungry. And even if they did, the hack-job behind the cover is now their problem. And no way will I ever revert myself.

ANYWAY, what I would really like to do is use this as an excuse to buy a Sawzall and do the job myself. Masonry blade, shop-vac, and just notch it. Can you offer reasons why this won't work or why I'm dumb for thinking it will?

I know a grinder is another way to go, but I'm not loving the idea of tenting off the work-space. But I will if absolutely required. (I'm suspecting the hammer and chisel method might come at the risk of causing the whole bricks to crack off.)

Thanks
 
Regardless of method I would tent off the workspace. I haven't heard of doing this with a sawzall but you can be sure it will be dusty.
 
Regardless of method I would tent off the workspace. I haven't heard of doing this with a sawzall but you can be sure it will be dusty.

Thanks. I suppose it would still be prudent to do so. Reciprocating saw will naturally be dusty. But they won't kick out the rooster-tail of debris that a grinder would.
 
It loos like there is a pretty big surround on that thing, or can be. So yeah I wouldn't worry too much about butchering the arch, apart from resale if you ever want to take the stove out before selling the house. What's above the brick above the arch?


montlake-room-1.jpg
 
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Personally, I would look for a stove that fits. Or take out the entire row of bricks and find a stove with a surround that covers it up. Minimum clearance is just that....minimum. A little extra wiggle room is helpful.
 
It loos like there is a pretty big surround on that thing, or can be. So yeah I wouldn't worry too much about butchering the arch, apart from resale if you ever want to take the stove out before selling the house. What's above the brick above the arch?

View attachment 166022
On the front-side. Nothing. Goes straight up for probably 18 inches, and then notches in to form a mantel-shelf out of brick.

A little like this:
rebuilt-fireplace-custom-brick-mantel.jpg
 
Before I started cutting into that front arch I would get a consultation from a mason familiar with such bricklaying to get assurance that this arch isn't a critical structural support. Fireplaces with squared off openings usually have a steel angle iron lentil to support the brickwork above the opening. Since your photos do not show any such support it may be that this brick arch is providing the necessary structural support. The last thing you want is to weaken this area of the fireplace and possibly damage the brickwork above it.
 
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I am sure it is structural so anything you do you need to make sure you don't compromise the structure. And no a recip saw will not do it you need a grinder or circular saw with a diamond blade and a hammer and chisel
 
Aside from the fact you are going to destroy the gorgeous looking brickwork (you seem content with that part) the arch is what is supporting the rest of the bricks. You can cut it and it may stay today, but they will fall. Maybe today, maybe next month or maybe 5 year, they will fall. If you cut out the keystones you will need to have a mason repair the fireplace.

I would recommend finding a stove that fits and leave to brickwork to look at. Also would install a freestanding into the opening instead of using a block off plated stove.
 
As described by the OP, the arch only supports some additional veneer brickwork/mantel above (not veneer all the way to the ceiling) It's not structural in the sense of supporting the chimney itself or a building wall etc, but rather just the weight of the additional veneer above.
Assuming the mortar joints are sound, it seems doubtful that cutting 4" at most from the low corners etc. will cause the veneer above to fail, especially given there will still be a complete arch remaining, just of a lesser depth. If it's a concern, cut in some slots extending beyond the corners and let in a steel angle loose lintel.
To cut them, I'd probably cut a continuous level groove on the backsides and then wack 'em from the front with a large flat brick chisel to complete the cut.
 
As described by the OP, the arch only supports some additional veneer brickwork/mantel above (not veneer all the way to the ceiling) It's not structural in the sense of supporting the chimney itself or a building wall etc, but rather just the weight of the additional veneer above.
Assuming the mortar joints are sound, it seems doubtful that cutting 4" at most from the low corners etc. will cause the veneer above to fail, especially given there will still be a complete arch remaining, just of a lesser depth. If it's a concern, cut in some slots extending beyond the corners and let in a steel angle loose lintel.
To cut them, I'd probably cut a continuous level groove on the backsides and then wack 'em from the front with a large flat brick chisel to complete the cut.
I agree it is only supporting the face but that is still allot of brick and yes if done right you should be able to remove some of that arch without harming the structure. But cutting a slit and then breaking the rest of it is not the right way to modify brickwork that is supporting the face of a fireplace.
 
Score and break. Angle grinder with masonry blade. ...pick your poison. Former has slightly more risk for accidental damage of remaining brick than the latter, where you'd cut completely through. Somewhat depends on OP's comfort level, tolerance for additional repairs of accidental demo.
The real right way might be to take a long term view...if someone wants woodburning fp in the future, they'd dont want to discover a hacked arch...taking that view, then you'd deconstruct the arch and replace with steel lintel and horizontal coursing above, with brick and mortar to match existing.
In any event, the flat running-bond courses above the opening have a natural arching effect, so the entire structural load of the veneer directly above isn't necessarily supported by arch.
OP, let us know how it goes. Don't forget to check the insert's minimum width requirements for back of fireplace & the hearth extension protection requirements (looks like current hearth extension is 16"). Good luck!
 
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In any event, the flat running-bond courses above the opening have a natural arching effect, so the entire structural load of the veneer directly above isn't necessarily supported by arch.
Agreed but i think advising a homeowner with obviously little to no masonry experience to modify the the supporting structure of a fireplace face especially by scoring it and breaking it is very irresponsible. And i am sorry but it would not take allot to compromise that single thick brick face that the op showed.
 
As described by the OP, the arch only supports some additional veneer brickwork/mantel above.
I can find no place that the OP mentioned veneer. In the pictures it is clearly bricks and not veneer bricks, you can see it on the inside of the chimney. I do agree if he is going to cut the support structure out from the arch a lintel would be recommended/required. Pounding on old bricks is a real good way to knock mortar loose. Pulling apart old brickwork can usually be done with a 2 pound mallet and gentle tapping.
 
I can find no place that the OP mentioned veneer.
It is a veneer of full brick over the actual structure of the chimney. But that arch is still supporting that face structure.
 
As described by the OP, the arch only supports some additional veneer brickwork/mantel above (not veneer all the way to the ceiling) It's not structural in the sense of supporting the chimney itself or a building wall etc, but rather just the weight of the additional veneer above.
Assuming the mortar joints are sound, it seems doubtful that cutting 4" at most from the low corners etc. will cause the veneer above to fail, especially given there will still be a complete arch remaining, just of a lesser depth. If it's a concern, cut in some slots extending beyond the corners and let in a steel angle loose lintel.
To cut them, I'd probably cut a continuous level groove on the backsides and then wack 'em from the front with a large flat brick chisel to complete the cut.

While my engineering expertise is limited to metallic and composite structures, I'm generally holding a similar mindset.

uRRo1LU.jpg

The face of the fireplace isn't on the same plane as most of the above structure. So most is not all of the load-path due to gravity isn't going to through that face. Moreover, sawing off ~2"-3" of the voissoirs and shaving the keystone a hair should still leave plenty of brick to react whatever compression loads are in the structure.

Q8QehDH.jpg

Naturally, I will await the mason's opinion before going after it with tools. Thank you to everyone so far with the inputs.
 
You should be able to do that as long as you dont disturb the rest of the brick in the process. And yes i agree that arch is not supporting the whole chimney but it is supporting the brick above it so caution is required
 
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Gentlemen,

Very brief update, in case anyone in the future stumbles across this thread. The the demo-work was performed with a masonry-blade in my Sawzall and my cheapo-angle grinder with a 4.5" masonry cutting wheel. The grinder wasn't large enough to make a full-cut. But was handy at creating scoring cuts to get the sawzall started, and creating a cut-line that didn't become obscured with brick dust. Though it did throw far more dust than the saw.

All things considered, buying a large 9" or so grinder from Harbor Freight ($65 before coupons) might have been easier on the muscles than a reciprocating saw, but we managed. Tenting around with old bed-sheets helped keep dust down, but there was expected cleanup afterwards.

Anyway, no problems. Tenting and cleanup took longer than cutting itself. I'll likely pop back in for a final update after the install is completed next week. Thanks again, everyone.

hcXfmdC.jpg
 
Nice job. And interested to see how that insert works. First I have heard of'em.
 
Just looked at the website. It appears that Country Stove has a new name.
 
Just looked at the website. It appears that Country Stove has a new name.
Yes, the old Lennox lines are now owned by IHP. Country stoves are now under IHP IronStrike. The BIS Traditions ->Lennox Montecito is now under the IHP astria brand.
 
I can't figure out why Lennox buys stove companies. The always turn around and sell'em.
 
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