I use the same insulation (just the 1/2" version) for my glass tanks and it works wonders. It's not the "best" look, but it does the trick. Helps my electric bill too.
yeah before the weather turned i didn't need anything additional with it. then winter hit and i tried running a space heater, and that just wasn't worth the cost of the electricity.
it may not be the prettiest rack, but my snakes are happy and so am i.