Fiber Cement Siding for Wall Heat Shield

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RodS.

New Member
Aug 19, 2020
3
Iowa
I'm wanting to install a wall heat shield as easily and cost effective as possible. I know NFPA allows a 1/2" noncombustible cement board with 1" spacers, but my question is whether I can install 5/16 exterior fiber cement lap siding or panel over top the cement board for aesthetic purposes. The technical specs on Allura fiber cement siding state it is noncombustible and Type A fire rated. Just checking if anyone has used the product before. Thanks!
 
Should be good, just make sure that the board is stood off on spacers to allow air to rise between the inside on the board and the outside of the wall
 
If it's non-combustible it's fine. Remember to start the wall 1" off the hearth floor and leave it open on top in addition to the 1" air space behind it.
 
How much space between the ceiling and top of the wall shield is recommended? Is 1" like the bottom sufficient? Thanks!
 
Before driving yourself crazy, do you even need a wall shield? Very few installations actually require one but many people are under the false impression that the wall behind the stove and beyond the minimum clearance to combustibles must be built as an NFPA wall shield.

I have painted sheetrock 6.5" behind my stove.
 
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How much space between the ceiling and top of the wall shield is recommended? Is 1" like the bottom sufficient? Thanks!
Yes. 1" open at the top is the minimum.
 
Before driving yourself crazy, do you even need a wall shield? Very few installations actually require one but many people are under the false impression that the wall behind the stove and beyond the minimum clearance to combustibles must be built as an NFPA wall shield.

I have painted sheetrock 6.5" behind my stove.
Good point. Is this for clearance reduction? What stove and what is the requirement vs the goal with the reduction?
 
Good point. Is this for clearance reduction? What stove and what is the requirement vs the goal with the reduction?
Yes, I’m looking for a clearance reduction. I had a used hearthstone heritage 8020 corner installed earlier this summer with a rear heat shield. Upon further inspection, I realized my single wall stove pipe measured less than 18 inches from each adjacent wall (16-17 inches). I figured adding a wall shield would offset this mistake for safety and my homeowners insurance compliance.
 
Yes, I’m looking for a clearance reduction. I had a used hearthstone heritage 8020 corner installed earlier this summer with a rear heat shield. Upon further inspection, I realized my single wall stove pipe measured less than 18 inches from each adjacent wall (16-17 inches). I figured adding a wall shield would offset this mistake for safety and my homeowners insurance compliance.
An easier solution might be to switch to double-wall stove pipe. It has 6" clearance requirements and will keep the flue gases hotter for a cleaner flue.
 
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