I'm building my first pizza oven from a DomeOvens modular kit. The stand will be a 4" concrete slab on top of cinder blocks. I have 2" of ceramic fiberboard bought from McGills. Question: under the fiberboard base how much perclite with cement should I use? none? 2 inches? 4 inches? Thanks!
Minimum 4" unless you are using vermiculite then its 4.2"