Insert Installation Plan Check

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EmberEnergy

New Member
Aug 18, 2021
26
Silver Spring, Maryland
Hi All,

I'm gearing up to install my Kuma Cascade LE insert and wanted to run a sanity check by here. Insert will be put into existing masonry chimney at floor level (not a raised hearth). The back of the chimney is in our uninsulated block single-car garage. I want a code install, the most energy efficiency, and get a sensible order of operations.

1) Chimney rebuild roof up. Contracted mason is doing this work. And cleaning chimney.
2) Remove damper
3) Knock out terracotta tiles (should I do all or only ones needed? Was leaning to do all.)
4) Drop 6" Champion hybrid flex pre-insulated liner (open to other suggestions, esp for heavier pre-insulated)
5) Stuff insulation where damper was (best insulation?)
6) Install damper block-off plate
7) Install new hearth extension (some low R-value slab with at least 1.4 R-value underneath if the existing concrete pour doesn't come out far enough for spec)
8) Any other insulation or method to keep heat in?
9) Install insert, may leave off surround, but have one for it
10) Profit

Any recommendations on most effective insulation for both above damper plate and under hearth slab appreciated.

Thanks all.
 
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NoGoodAtScreenNames

Feeling the Heat
Sep 16, 2015
416
Massachusetts
For the block off plate most people use rock wool / Roxul or whatever is available in your local box store. As long as it’s high temp rated you should be ok. I liked using Roxul for mine as it holds it position and was forgiving of my inability to cut a proper sized hole in exactly the right spot where the liner poles through.
 
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kborndale

Feeling the Heat
Oct 9, 2008
311
LI
#1 should be to have a years worth of dry wood ready to go so you don't go thru all the trouble of a proper install and still don't have a stove the operates properly.
 
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EbS-P

Minister of Fire
Jan 19, 2019
1,465
SE North Carolina
#1 should be to have a years worth of dry wood ready to go so you don't go thru all the trouble of a proper install and still don't have a stove the operates properly.
Or consider a pallet of sawdust bricks/logs part of the install cost.
 

brazilbl

Burning Hunk
Aug 24, 2017
118
El Dorado County, CA
I second the idea of buying a pallet of compressed logs in the beginning. Countless posts here regarding wet wood and its woes.
A pallet of them could last you a few weeks while you line up wood sources. At least for the first few weeks you will have reliable wood!
 

Caw

Minister of Fire
May 26, 2020
1,012
Massachusetts
If you're looking for an affordable way to make a hearth extension you can use Micore. It's made for sound proofing but has a high enough R-Value to work as a type hearth extension underneath a fireproof surface.


For example I have an Ember King extension providing the Ember protection with a micore cutout underneath providing insulation for the wood floor underneath.


You can see it under my house bear here, he loves to lay on the cold surface. I used to spray paint the edge of the micore black so it blended in more but it always wears off so I don't bother anymore. You don't really notice unless you're looking.

92560.jpeg
 
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EmberEnergy

New Member
Aug 18, 2021
26
Silver Spring, Maryland
Hello!

Regarding dry fuel, seasoned wood/compressed logs, I'm definitely on that train, agree 1000% (which is roughly the average moisture content of a bunch of dead standing ash that's been in the rain and I've been slow to split all summer).

I'll be burning compressed logs this season, and will work on a solar kiln to whip that dead ash into shape, and we'll see about next year, may do compressed logs for second year and I'm ok with that. I actually rather like the concept of compressed logs, other than the cost. Eventually I'll aim to hoard free wood (aside from labor) and will spring into action when I hear chainsaws in the neighborhood like EbS-P does.

Wet wood is not a fuel option and I will be getting a holster for my moisture meter so I can have standoffs every now and again with my wood stacks in the yard. The neighbors have no idea who just moved in next door,,,

Regarding floor insulation though, I'm looking for the highest R-value per thickness so I can keep as thin as possible underneath the extension. I've seen Micore, Lynn ceramic board, and mineral wool board, and for those it looks like I'd need about 3/4" to get to my required R-value of 1.4. I was hoping some miracle material of R=3+ per inch existed so I could be at 3/8-1/2" of thickness.

I am definitely burning wood this year so I'll need to make the dry fuel happen, otherwise with the amount of time I've sunk into research and non-stop talking about it, my wife will put me in that stove, my moisture content aside.
 
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Caw

Minister of Fire
May 26, 2020
1,012
Massachusetts
That's interesting you need R = 1.4 for an extension. My stove notoriously heats the floor in front of it but only requires R = 1 so I have the powdered steel Ember King with 1/2" Micore 300 underneath.

Micore 300 R = just over 1, like 1.03 if iirc
Micore 160 R = around 1.3

The stove store/installers said just the Ember King was fine of course. I decided to measure because it got very hot and before adding the Micore the hardwood floor would get like 140 degrees which is way too hot. Now it never gets above 90. I'm happy with it especially considering a 4x8' sheet was $29!
 
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EmberEnergy

New Member
Aug 18, 2021
26
Silver Spring, Maryland
Just posting some updated pictures. I was so hesitant to start breaking up this tile cause there was no turning back but I was pleasantly surprised to find stonework underneath - it looks pretty nice I think.

Too bad it's only 16" out before the sub-floor begins and I need like 19". I'm probably going out to 24" from the brick face and will use Micore 300 if I can't find Micore 160 and find a nice slab to put down.

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