Extruded Styrene / Styrofoam

[TCWORLD]

It has less to do with hot climates and more to do with whether the houses in that area have basements. As I understand it, foam is typically used to insulate basement walls. Here in Arizona, you can get blue foam in 1" thick sheets at the local home center. I haven't found a source for anything thicker.

In the UK, (I know not really helpful) you can get Styrofoam up to 6" thick. The stuff I use is made by Dow Chemicals. They probably sell the stuff in the US aswell. I hope you can find some.