Ceramic board layout 42" Pompeii

[Unknown_element]

Anybody have a picture or drawing of the board under there 42" Pompeii??? Confused on how much I need to buy

[UtahBeehiver]

My Ca Si sheets were 12 x 36 and staggered joints. The black insulation under the CaSi is FoamGlas insulation which will not absorb water.

[Unknown_element]

The first layer of firebrick doesn't need to sit on the insulation?

[JRPizza]

I used a cad program to do much of my layout, including how to fit my board in under the dome. The attached link shows how I did it. I used 2 layers and was able to make the second layer a mirror image so that most of the seams didn't align, although I don't know if that makes any difference or not. You will undoubtedly end up needing to cut some of the board. I used a sawsall and wore the respirator the family bought me for the build.