Ever since I got my chickens, about a year ago, they have been sleeping in the nesting boxes. I don't like this because they sleep and lay on the poopy bedding. I'm going to re-construct my coop -- should I encourage them to start using the roost at this point by blocking off the nesting boxes at night? I know to put the roosting perches up higher than the nesting boxes. I am in Oregon and it can get kind of cold (lowest around freezing). Also, one of my four birds has a little bit of a limp. I am concerned about her ability to perch on a roost all night and the cold. Suggestions? Thanks!!!!