Go to the "coops" section of the forum and look at how others have their roosts set up. If you can build long roosts parallel to the floor so your birds can roost side by side instead of stacked on top of each other, they will be more comfortable. Every chicken instinctively likes to be on the "top bunk," so to speak. Being lower than another chicken means you can get pecked, and that's no fun. So they'd rather be on the floor, it's safer and more peaceful. At least it's safer from the other chickens. But if you have rats - not so much.
