USG Durock safe for fireplace wall?

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New Member
Jul 21, 2020
Chicago, IL
Hello all,

Does anyone know or can anyone comment on whether or not it’s advisable to use USG Durock on a fireplace wall/surround as a substrate for stacked stone - specifically, above an EPA high efficient wood fireplace?

I feel silly asking, but USG’s user guide specifically says that Durock shouldn’t be used for an application that exceeds 200 degrees F.

Durock seems ubiquitous in our world, but now that I think about it, every application I see Durock is either on a wood stove hearth or a gas fireplace surround, not a wood burning epa fireplace wall.

Its considered non-combustible and tested to ASTM 136 which tests to a much higher temperature than 200 degrees Fahrenheit. Should I just skip the Durock altogether and use hardibacker 500 instead? I always considered Durock the superior product due to the fiberglass mesh, but now I’m second guessing that.



Staff member
Nov 18, 2005
South Puget Sound, WA
Durock uses perlite or pumice to lighten the cement board. It is commonly used in this application.
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