Hmmmmmm, I was leaning towards deep litter for the floor of my semi-open air coop/run but now I don't know, maybe sand. I was also thinking of a poop board sprinkled with bokashi but now it maybe better with a hammock. I do plan on having a clear solid roof over the entire area and so rain won't be a problem. We kept the logs from some trees we felled when they died so that should help keep things interesting for them.