We're almost done with our coop. It's a 4x8 house on stilts with a 3' wall in the back and a 4' wall in the front. We'll be housing 4 barred rock hens and 4 buff orp hens. We live in Colorado, where it can get pretty cold in the winter (-17 two nights this past winter). I'm thinking of putting a divider in the coop to make the "winter coop" 4x4 so that they have a smaller area and can presumably heat it a little better with their residual body heat, but I can then remove it in the spring/summer/fall to make it a bit more spacious. Any thoughts? Am I being overly concerned?