I am a "new mother" to our four chickens. Our girls were born on May 5th, 2013 so they are 26 weeks old. We got them when they were a day old on May 6th. We have a Black Australorp (Muffin), Buff Orpington (Nugget), Silver Laced Wyandotte (Oreo), and an Americauna (Peanut). Against what some people advised, we chose to keep their brooder in our house. We chose to do this because of the extra time and interaction we would have with them. They moved outside after all of their feathers came in. We constructed a roughly 4x4 coop. It was constructed with typical lumber and plywood, with insulation and then paneling for walls. There is also siding on the outside. (Pretty well insulated!) We live in Wisconsin where it can get down right cold during the winter. Right now, our lows are around 20F and highs around 35F. We clean the coop weekly- taking out everything and starting fresh. Here are three pictures of the coop. We put a 14x6 wall vent in the big white door. I'm hoping it's enough ventilation but don't want to lose one of my girls because of it.