I have three hens (of unknown breeds) that I free range all day, they go into the coop (and fully enclosed run) at night. Normally, I leave the inner coop door open, and obviously, close the run door at night. The coop is only 3x2.5, with attached nesting box-3x1.5') This is my first winter, and I don't know if I should close the coop door, due to the cold. I am afraid they are too exposed to cold air if I leave the slider open. I closed it last night, there wasn't any condensation on the exterior window this morning, and the girls had actually pushed the slider open and let themselves into the run by morning. That is the perfect solution, IMHO, but I don't know if that was a freak "accident" or if they will do that each morning. (I live in TN, so our nights are only down in the mid 20-30's) I appreciate thoughts on whether to close, cover, etc. I also wondered about hanging wide plastic strips over the opening? Thanks in advance!