I use these for bantam breeding pens, 3 feet by 3 feet by 2 feet high. for larger birds I would go 3x4x3. for a pair or trio. if they are going to be in your coop plywood would be fine for the roof. ok for some reason It wont let me post the picture. they are basically just 2x4 frames. I used metal roofs because I also use them for quarantine pens.