You might still want to build a room with 2x4s and insulation. This is the first thread I made of the room I built. It's roughly 7' by 8' and with framing, insulation, electrical, drywall, and anything else relating the the room, the total cost was like $225. Not bad. So just thought I'd mention that if you haven't considered the full cost of building a snake room.
Here's the link with the pics from the beginning of the snake room... http://ball-pythons.net/forums/showt...-snake-room...