I have read through multiple posts about chickens not sleeping inside the coop, and I still can't seem to pinpoint why our hens will not sleep inside the coop. They used to sleep inside the coop, then this summer when it was incredibly hot, they started sleeping on the run roost. Now that its cooler, they still prefer to sleep outside. I clean the coop and run every 2 weeks. There are no rodents. No signs of mites on the birds. I tried corralling them into the coop at night for two weeks straight to remind them to roost there, and as soon as I stopped forcing it, they went right back to sleeping outside. I took the ladder away from the outside roost and two or three would sleep inside for a few nights; now all five are back outside. The run is secure. I have no concerns about predation. Quite frankly, I just prefer they utilize the coop at night (it will get cool (lows of 35-40) here this winter, but nothing threatening to a hardy chicken. They do go inside the coop during the day. They have food and water both in the run and in the coop. They have plenty of space on the inside roost as well. If it matters, they get let out to free-range for typically an hour a day, in the evening (we have a major hawk issue, so they are now limited to supervised outings only). I'm tempted to take the run roost down (they never use it during the day, anyway) and see if they start roosting inside. They are six (ish) months old and have been housed in this run/coop since 6-8 weeks.