This is more of a behavior question. My 5 hens (10 months old now) prefer to roost outside of their coop at night and now that it's getting colder here (mid 20's at night) I'm wondering if I should force them inside their coop? My coop is 4'x5', has 2 roosts and 2 nests for the 5 young hens. The coop entrance is the typical 12" square opening without a door. Inside there is a themoswitch that turns on a heat lamp at 35F and turns it off at 45F so it is cozy enough in there to keep their water from freezing. The hens have slept inside on a few cold nights that are windy but not on cold nights that are calm. Are they smart enough to go inside when it dips into the teens on calm nights? Or should I herd them inside and attach a door? Be glad to offer more info if needed. Thanks for any advice!