Here’s my roosting set up. A flat top surface works best, but a lot of things can work. Chickens, unlike parrots, like to sleep flat footed, not with their feet wrapped around the bar. The flat surface, like a 2×4, allows them to keep their feet warm on cold nights by sleeping on them. I have a poop hammock, instead of a poop board, but it’s pretty much something underneath the roost bars to catch poop that’s easy to clean.