While the Cortile Barile oven kit comes with the foam EPS panels that are used as the insulation layer of the pizza oven base, the Mattone Barile / Grande and the Mattone Cupola kits do not.
To be honest, by placing the 2 hearth base slab panels w/ the Cortile kit, we were able to save on shipping / packaging by shipping in 1 box size instead of 2 different box sizes.
Not to worry!
4’ x 8’ x 2” EPS foam sheets are sold at all Big Box hardware stores like Home Depot, Lowes & Rona (not True Value or ACE – sorry).
You can find the panels in the Millwork section or in the Garage Door section (the panels are used as garage door insulation.