Air gap- vermont castings dauntless

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New Member
May 2, 2023
Portland, Oregon
Hi everyone! I am installing a vermont castings dauntless woodstove in my tiny living room so I am hoping to reduce the stove distance from the wall as much as possible. The stove will be installed in a corner and I am planning to do a wall with an air gap. Right now the wall is just studs with insulation. To do the air gap, I am using 1 inch spacers directly along the studs and then attaching the durock to the spacers. What thickness durock do I need to use? Also, I know there needs to be a 1-inch air gap on the top and bottom of the durock, but how high do I need to install the durock? And how wide along the walls? Does the corner install require anything special?

Photo of space attached, heat vent is getting removed.

Thanks for all the help!

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I am not seeing a clearance reduction allowance for an NFPA wall shield in the Dauntless manual. The lowest clearance is the one listed for double-wall stove pipe.

PS: Verifying this is for the Dauntless. The title says Defiant.
Sorry about that, it is for the Dauntless. Is it safe to assume if the manual does not show a clearance reduction for an NFPA wall shield that it is not applicable? We will be doing a double-wall stove pipe.
No problem, fixed. The NFPA 211 clearance reduction table is mostly for unlisted stoves. It can not be used unless permitted in the manual, and then only to the tested reduction listed in the manual. Some manuals do allow the local inspecting authority to permit a clearance reduction but they often want documentation to verify the safety of the requested reduction.
Thanks for the info! I ended up calling Vermont Castings and you are correct, installing with an air gap is not an option with the Dauntless stove.

I have started building the hearth pad along with brick on the corner walls. I would also like to install a wood mantle but am finding limited info regarding clearances of the mantle to the double wall pipe with vertical installation. Figure 3.9 of the manual shows 12" clearance for the stove to a combustible wall. Should I assume 12" is also a required clearance for a double wall pipe to the mantle?

Air gap- vermont castings dauntless
The mantle clearance to the stove remains the same and has priority. The clearance to a vertical, double-wall stovepipe is typically 6". One option would be to have a non-combustible mantel. Then the clearance issue is moot.