On May 25, 8:15*pm, "Bob F" wrote:
GIANT SNIP

http://foamular.com/assets/0/144/172...4f08-bebe-71f4...

FWIW, I got 6" of extruded Styrene under my 4' deep concrete hottub, which has
held up fine for 20 years or so, so far.

FWIW, I got 6" of extruded Styrene under my 4' deep concrete hottub,
which has
held up fine for 20 years or so, so far.

+1

Great first hand data!