Converting from ZC to stand alone wood stove

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Marcuslawton5

New Member
Jan 30, 2022
4
Doswell, VA 23047, USA
We are replacing our zero clearance wood stove with a stand alone Quadra fire aisle Royale wood stove. I have ripped out the old ZC and prefab hearth and laid porcelain tile. My question is can i tie into the existing 12" double wall pipe? The pipe is 12" outer with a 8" inner stainless steel pipe. I need to adapt it to 6" single wall but the over the shelf adapter won't fit the stainless pipe. Then i still the problem of how to cap off the void between the 12" and 8". Anyone else done this? Anything commercially available? Ive spent hours looking and can't find anything.

[Hearth.com] Converting from ZC to stand alone wood stove
 
The old air-cooled ZC chimney pipe is not approved for woodstove use due to its lower temperature rating.

Note that the Isle Royal is strongly radiant. It puts out a lot of heat. The hearth will need improvement so that there is 16" behind the stove and 16" of hearth protection in front of the stove door. The hearth needs to have an R=2.2 rating.
 
Thanks! I have the required 16" back and front. I used fire rated concrete backer board and porcelain tile. Also used radiant heat approved morter. Just trying not to spend a fortune in new pipe. The old ZC was a Xtrordinair catalytic wood stove. It got pretty hot before it burned itself out.
 
If there is 16" behind the stove then it's ok. The clearance is to the nearest combustibles which in this case are the studs behind the cement board. The front looks shy, but maybe that's the camera angle. What is the hearth construction? R=2.2 is a fairly high insulation value requirement.

I helped install a T6 at a neighbors that had the same setup, with the same FPX that was burned out. They replaced the chimney pipe. It was HT1700 instead of HT2100. They also found out that the FPX chimney was installed without a firestop in the chase.

[Hearth.com] Converting from ZC to stand alone wood stove
Note the generous hearth.
 
Same deal on the bottom. I also put a stove pad down per the manufacturer's guidance.
You might want to check the R value of the stove pad you used - the backer board and tile will get you around R 0.45, so you'd want something at least R 1.75 to get to a total of R 2.2. While some hearth pads have that, I don't think they all do, and the one in the photo looks pretty thin.

If it's not sufficiently insulative, but is fairly rigid, you could add two half-inch layers of micore under it and that will get you the insulation you need.
 
While it may be a bummer, it's the right decision. Think of.all the nights you'll be laying thinking about whether it's safe to go to sleep... (Knowing it won't be).

Safety is important. The peace of mind that goes with it is incredibly consequential too.
 
You can't fit in a 6" flexible stainless liner? Is that where the shelf adapter screws things up?
 
You can't fit in a 6" flexible stainless liner? Is that where the shelf adapter screws things up?
I thought about dropping down a preinsulated 6" DuraLiner, but then how is that weight safely supported in a way that doesn't look like a hack and would pass inspection?