Hi, Im new to the forum and new to chickens. Whoopppeee--been waiting years for this!! My husband is building a raised (waist level) portable coop on wheels to house the 4 chickens we plan to buy next week. We are trying to figure out the coops floor. Right now its ½ x ½ galvanized wire. My husband is going to make a (hard) plastic liner, possibly sectioned for easy removal. I wish I could fill it with sand but then it wouldnt be movable!! Guess well settle with shavings. How deep should the liner be to keep the chickens happy and the smell down? Thanks!