I need to try to insulate a cat house/box just for temporary use. I
want to be able to use material I have around the house rather than
buying something since it will only be used for a week. Right now I'm
using a cardboard box as the cat house and I'd like to inuslate the
sides, top, and back. Will either of these materials work and if so,
which one would be best: carpet or styrofoam that's commonly used as
packing material for VCRs, DVD players, TVs, and computers.

I had originally wanted to buy some styrofoam insulation from a
hardware store but the stores around here either don't have it or it
costs way to much. Plus, the sheets would be to big to fit in my car.