Go to your local lumber yard or home depot or lowes and buy a piece of foam insulation board. You can get it in 1in thick or 2in thick. Its up to you. But i had this problem and both pro products and repti-racks suggested i do this and now my temps are perfect. I put a piece between the floor and the rack, then between my rack and my cage and then a piece in the back that is squished in between the wall. It helps ALOT. And its only about 9 bucks for a 2x8 piece.