I'm getting ready to remodel my bathroom and figured I would replace what
was placed in the exterior walls and called insullation back in 1957 (one
inch of fiberglass mat). I was looking at either the rigid pink foam or
styrofoam insulation. There is a big difference in price for 4x8 sheets but
only a difference in 2 R value. I've read what I could and still don't
understand what a difference of 2 R would make. Can someone explain or
point me to a site where in REALLY simple terms I can find out what an "R"
really is?