The proposal sounds good. You need to work us up a preliminary sketch on a bar napkin.
A couple of thoughts here.....the insulating properties of air trapped in a double wall situation is really good on it's own, I wonder if you only need to have the ceramic around the bottom? Would sand be easier to work with? Also wondering if something like Kaowool wool would work. It would sure be lighter.
KCBS - CBJ
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