Tips on safe and efficient heat shield with Durock cement board and brick veneer

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HearthsAndMinds

New Member
Nov 17, 2019
9
Washington, D.C.
First time posting here, so appreciate any patience you all can afford.

I recently came into a free Dovre 300GH, which after scouring this forums, it appears no one has any good information on. Luckily it's got a UL data plate with clearances, etc. and looks to be from about 1986 based on stamps in the cast iron.

I'm attempting to reduce the clearance per NFPA 211 standards by using 1/2" Durcock cement board, mounted to my combustable drywall using 1" ceramic spacers. My question is whether I need this shield to be open to air flow on the top, bottom AND sides? I only ask because I'm covering it with some brick veneer for a nice look and would like to cap the sides of the heat shield so the gap is not visible.
 
Top and bottom need to be open at least an inch.The sides can be closed. Instead of spacers you can cut 3" x 3' or 3" x 5' strips from the sheet of 1/2" Durock and double them up to make 1" thick firring strips. Screw them vertically to the studs as your spacers. Then attach the full sheets of Durock.
 
Top and bottom need to be open at least an inch.The sides can be closed. Instead of spacers you can cut 3" x 3' or 3" x 5' strips from the sheet of 1/2" Durock and double them up to make 1" thick firring strips. Screw them vertically to the studs as your spacers. Then attach the full sheets of Durock.

Thank you so much for the quick advice! And to be clear, because there is no manual for this stove anywhere (I found a 300G manual in dutch somewhere online, but it has way different clearances than the data plate on mine), I assume any inspector would defer to either the UL plate or the standards for a non-listed stove i.e. 36"? So even if my data plate says 36 inches, this heat shield should be able to allow me to reduce to 12 from stove to combustable wall?

This stove also has threaded holes in the back of the stove with 1" ribs for stand off... (picture attached) I'm assuming I could also just fabricate a 28 guage sheet metal heat shield and screw it in, no?

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Is it possible/legal to reduce clearances specified on the stove plate using an nfpa wall shield? I know you can use the shield to reduce the nfpa baseline clearances which are like 36”!
 
Is it possible/legal to reduce clearances specified on the stove plate using an nfpa wall shield? I know you can use the shield to reduce the nfpa baseline clearances which are like 36”!
Great Q, that's kind of what I'm wondering here. The data plate (picture below) appears to be showing 36" to a combustable wall. Much of what I've read indicates that if you do a proper heat shield, it can reduce any clearance by 66% (i.e. 36 down to 12) regardless of what the plate says, which again, is assuming stove to combustable material... (?)
 

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Imagine some modern stoves like my bk that only require 6” to combustible wall. A little sheet metal and it could be 2”? I don’t think it works that way.

I seem to recall that unless the owners manual for that stove allows for a clearance reduction specifically in its manual then the listed clearances are non reducible.
 
Imagine some modern stoves like my bk that only require 6” to combustible wall. A little sheet metal and it could be 2”? I don’t think it works that way.

I seem to recall that unless the owners manual for that stove allows for a clearance reduction specifically in its manual then the listed clearances are non reducible.

It seems there’s a maximum you can reduce to, 12”. My data plate on my UL Listed stove says 36 so I’m hoping I can still reduce to 12 with proper heat shield.

http://nasdonline.org/1248/d001052/wood-stove-installation-and-operation.html

“CAN RADIATING-TYPE WOOD STOVES EVER BE INSTALLED LESS THAN 36 INCHES FROM COMBUSTIBLES?

Yes. If a UL-listed stove has a heat shield attached, the clearance can be reduced as specified. Or build a heat shield to be mounted 1 inch off the wall on non-combustible spacers. To reduce the standard clearance to 12 inches, the heat shield should be of 28-gauge sheet metal, mounted off the floor to provide unrestricted circulation of air between shield and wall (see Figure 1).”
 
Imagine some modern stoves like my bk that only require 6” to combustible wall. A little sheet metal and it could be 2”? I don’t think it works that way.

I seem to recall that unless the owners manual for that stove allows for a clearance reduction specifically in its manual then the listed clearances are non reducible.
12" is the limit unless tested and documented elsewise in the manual.