Covering dome with stone

[limestone]

I plan to cover my insulated vermiculite/portland layer with stone keeping the dome shape. Can I mortar directly to the insulating layer or should I cover the insulating layer with diamond mesh first. Should I cover the insulating layer first with anything to allow slip or expansion?

[azatty]

Re: Covering dome with stone

Put metal lath over the dome first, then a "brown" coat of the base stucco (vermicrete in this dase). Let it cure before you put stone on it. The stone needs some structure to support it if you don't want it to compress your dome insulation. It will also allow for expansion of the dome.