Our coop is raised about 2 feet off the ground and is approx 4x6. We usually leave the main door to the coop open during the day so the chickens can go in/out as they wish (the coop is enclosed by a 6 foot chain link fence). During the cold weather should we put some plastic or something in the opening that they would have to walk thru to get outside. We live in Nebraska and it can get quite cold here in the winter. The coop door faces the south so shouldn't have too much wind going directly into coop but don't want the chickens to freeze either. It rained and snowed today and all seemed to be fine, the chickens didn't come out of the coop at all. First winter with chickens and really would like to still have them all next spring, so any input would be appreciated!