I have a range of different breeds, some with big old combs. A couple have already gone through their first winter. Our coop has a window on each end, that we've propped open during summer, that we intend to start closing when temps drop into the 50's at night. Around 3 sides at the top is open venting (with wire to keep them safe of course). Across the front I'd say the ventilation space is around 6 or 8 inches high, and on the sides, it slopes down to nothing at the back. Plenty of ventilation for summer, but I'm concerned about winter. Their roosts are a good 2 feet off the floor, placing their heads at a point where they can extend their necks and actually look out the space. What I plan on doing during nights where there is going to be a cold wind, or when it's just going to get pretty cold, is to drape a tarp over the roof, sticking out enough to block the direct wind while still allowing for ventilation. But it does get cold around here from time to time at my elevation (Smoky Mountains). Extended periods of sub freezing weather isn't unheard of, but it's not the norm. I've read about dubbing to keep large single combs from getting frost bitten, but I'm soooo not going there. I've also heard that you can bag balm the combs at night to keep them from freezing. I'm also considering a low wattage heat lamp on a timer that would keep them a bit warmer during the coldest parts of the night. I've inspected a lot of "coops" in my area, and found that tons of them are just wide open to the elements year round. Maybe weather losses just become part of owning chickens to them? I don't know. I'd like to hear from people in a few different zones regarding how you deal with colder weather. If I go the heating lamp way, should it be a certain color...can they sleep correctly with a light on? Any advice is greatly appreciated, as I want to start planning. We've already put 90 degree weather behind us, and there are some nights coming up this week in the upper 50's. Means cooler weather is right around the corner! Thankfully!