My input on cement board for a new hearth

[Beetle-Kill]

Real quick, yanked out an old stove, put in a new one. Said "Oh, what the heck, build a new hearth." So of course, the new hearth has to have multiple radius's and elevations. 3 to be exact(at this point). To date I've used 1/4" Hardi-backer-, 1/2" USG Durock Nex-Gen, and 1/2" Permabase. Now my point- the first two cut without problems, either with a ute. knife to score- or a jigsaw(remember-radius cuts). The Permabase on the other hand is a real SOB to cut. I initially cut templates out of the stuff with a grinder and cut-off disc, but it was kicking out sparks and eating the discs. Tonight, I'm cutting some final pieces, and the Permabase ate 2 Bi-metal jigsaw blades in about 8" of cut. Scorched my thumb on one blade taking it out of the saw. So the FYI is that this stuff is steel strand re-enforced, nice and stout, but a real bear to cut clean. Good luck, I'm out until tomorrow. JB

 

[Beetle-Kill]

Oh yeah, before anyone say's-"Why did you use the different board?"- It's because I had it on hand and it fit at the time. There ya' go. :lol:

 

[begreen]

Permabase is not suitable for a hearth according to the manufacturer. Though considering the BK King stove only needs non-combustible, it will probably be ok. Just not ok if a different stove with higher RValue requirement is later installed there.

"PermaBase Cement Board
should not be exposed to
temperatures over 220°F
(105°C)."