I'm planning my countertop right now. It will be a skim-coat concrete countertop (using ardex feather-finish), and the test sample I made looked great. What I'm wondering is the makeup of the countertop, as there will be 2 weber kettles suspended from it (a 22.5 pizza kettle and the 26 for everything else). My sample used 2 layers of 5/8 plywood (roughly, danged metric...) and a layer of concrete backer board, and it was heavy and solid enough to dance on.
My concern is obviously around the kettles - I will be attaching a ring of steel (wine barrel hoops actually) in the countertop holes, and dropping the kettles on the rings. I'm wondering if plywood is the wrong way to go for heat/burning reasons, or will the steel ring be enough to shield it?
I've considered 2 options - 1 is making the plywood cutouts 1/2-3/4 of an inch wider than the hardibacker and concrete will be to have some air gap, the other is just doing the entire countertop with 2-3 layers of backer board (hardi, durock, perma - whatever). I'm worried that if I make the underlying plywood cutouts too big, the concrete board and skim coat that's unsupported will flex and crack over time...
Seems like there are downsides to every option I can think of. :shrug: