wall shield thickness

[larry08]

Hi there,
I am looking at getting a new progress hybrid to put in a corner of my living room. After reviewing the clearances in the manual, it looks like the way it would fit best is to mount parallel against the wall and put up a heat shield on the adjacent wall. This will reduce side clearances from 24 down to 12". I would like to mount some cement board and tile it, leaving a 1" airspace to the drywall. In the manual it lists that you can do this 3 1/2" thick masonry, but my cement board and tile will probably only end up being just over an inch thick. Would it still pass code to do it like my plan, or does it have to be 3 1/2" thick? The progress and hearth pad will probably weigh close to 1000 lbs. I cant imagine all the extra weight a 3 1/2" thick brick wall would add. I suppose I could just go the cheap route and use sheet metal, but really wanted something that would look nice

 

[Simonkenton]

I can't see what advantage 3 1/2 inches of masonry would have over the design you have come up with. I think cement board and tile will work fine.

 

[begreen]

There is a chart here that covers NFPA wall shielding options. A full masonry wall gives a 33% reduction. A ventilated wall shield achieves a 66% reduction. However, the minimum clearance allowed under this code is 12". The stove mfg. needs to invest in testing for lower than 12" and put the results in the stove documentation. Based on this you could make a wall shield out of sheet or decorative metal and it would qualify as long as it is on non-combustible spacers and is open at the top an bottom by an inch to permit the free flow of air behind it.
https://www.hearth.com/talk/wiki/nfpa-wall-clearance-reductions/