Hi - I am in the process of converting a 10 x 20 dog run into a chicken coop. We have put a wooden "playhouse" in one end of the pen to house the chickens . We will have nesting boxes in the house accessible from the outside. We have enclosed the top of the run with chicken wire. I need some advice.... The run is concrete with the chain link fence buried into the concrete. What should I use on the concrete? Shavings, dirt, sand? The chickens will also have free range time. The run is very shady which will be nice in the Georgia heat. Any advice is appreciated.