I am building a new coop and working on the design for the nest boxes. I plan to build two rows of boxes with 5 on top and 5 on the bottom. In looking at coop pictures I see some people have a bar that runs across the front of their top row of nest boxes for the hens to jump up on. Can anyone tell me if the hens end up using this for a roost? My top boxes will be approximately 4 feet off the ground with a 3 1/2" lip across the front to hold in the nesting material. Do they need something to "land" on? Any ideas?