We are making our chicken coop on an old 4'x8' trailer, we were thinking that if we have a grated floor, the poop will just fall through and we can keep moving the coop to fertilize our pasture. Has anyone done this successfully? We plan to build flaps to go around the bottom of the house to keep out drafts. The size of the holes would be about 3/4". Here is an example of the stuff I am talking about. http://www.brass-grilles-shop.co.uk/ekmps/shops/saunders/images/meb-ex_250.gif Any thoughts, suggestions? Thank you!