I just put together a Keter 4 by 6 shed. I will be using it as a coop for three new 18 weekers I am getting in two days. I want them separated from my three other hens for awhile. I am unable to put a roost attached to the wall or nest boxes as the walls are some plastic rubberized material. Any ideas? I will have a decent sized fenced in area for during the day. Only temporary...Any thoughts?