We are getting ready to build a tortoise shed for our leopards. Saw a nice rubbermaid shed at Lowe's with two locking doors and a sliding roof. The size is good, it would easy to clean, and it is nice looking. I am assuming it would need to be insulated. Does anyone have any experience trying to insulate one with this kind of roof? Insulating the sides would be no problem, and the floor, but the roof will be tricky to get it airtight. Sure could use someone with experience sharing what works, or what does not work. Haven't bought it yet. Thanks for your advice, pro or con.