Re: What Substrate for Quartz Slab on Kitchen Wall - Plywood or Hardi?
Is 3 cm the thickness of the slab, or the distance it will be suspended? If it it thickness, 1" is a heavy motor scooter. I would be worried more about vertical support than I would about a backer. However, I do believe I would install it on Durock. Definitely not plywood, and definitely not sheetrock. Neither have adhesion properties you will need.
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