Insulation

[Kaz]

Don't know if it has any thermal value. I really don't need it for fair weather camping. More for sound. What a beer I mean time consuming task.

[S. Heisley]

Yes, Kaz, it has some insulation thermal value. For example, If I remember correctly, the 3/4" Styrofoam has an R-5 rating.
Our camp trailers are so small that a little insulation helps a lot, both to keep it warmer/cooler and to muffle the outside noise.

[MtnDon]

FYI,
The pink and blue foams are R5 per inch.
The white bead board type usually R4 per inch.
The foil faced polyiso R6.5 per inch.