I will be putting my kitset coop together soon. It's one of those moveable ones so I can place it in different spots in the back yard (we live in an urban area). As far as I can tell, the run part has no actual "floor" so the chooks will be able to forage from the lawn. But on the inside, in the actual "henhouse" I want to know what I should use on the floor. Internet research has shown pine shavings to be popular. How thick do I need to spread it and how often will I need to remove the poopy shavings and replace with fresh ones? And can I use hay or lucerne chaff in the nesting boxes? (Apparently lucerne chaff is low in dust?) Any advice is very welcome. I'm a newbie and want to get it right from the start.