OK, so our family is looking into getting chickens for the first time. We have some old pig/dog pens that are all concrete. Part of the pen is inside of a cinder block building and the other part is outside. We are looking to enlarge the outside pen so that it goes out onto grass/dirt so that they can scratch. The concrete part of the pen is sloped and feeds into a drain for cleaning. The drain pipe is quite long and would clog easily so we don't want to put any shavings, sand, etc on the concrete floor. I saw where some people were saying that the shavings help for when the chickens get down from a nest box or roosting place. What about instead of putting shavings down we put down a rubber mat near the nesting boxes? They shouldn't need the shaving on the concrete to scratch in because part of the pen will be on grass/dirt. Does this sound workable? The concrete part of the pen would be about 6' by 12'. The dirt part can be quite bigger. Also, would we need to cover the pen? The outside part of the pen would be 6' tall. Thanks for any replies I get. We are excited about learning what to do. By the way, we live in central Louisiana so we deal with a lot of heat in the summer but now much cold.