I have an 8X10 sturdy metal storage bldg that I will use for chicken coop. I will have area on on both sides (about 10X8) for runs. All will be predator secure. My nesting area will be at back wall. Roosts toward front. My question has to do with protection against too much heat. I plan to insulate it. This week it has been in high 90's. Since framing of building is 2X4's, it will be easy to cut out panels and put wire in place. MY QUESTIONS IS: How much to I need to cut out? I plan to put vients at top of each end and replace the small window with wire. Is it better to have more "open" area or less? Thank you!