We live in Colorado, and when we first thought about raising chickens, I was concerned about how to keep them warm in the winter. Colorado winter storms can be brutally cold and windy, with the windchill often dropping well below zero. The last thing I wanted to do was build the chicken coop, raise the chickens, only to have them suffer frostbite, or worse yet die in the middle of winter.
After doing a lot of research, I found out chickens are actually quite hardy. As long as they remain out of the wind, rain and snow, they can survive quite easily. Armed with this knowledge, I designed the chicken coop with a few things in mind. The first thought was to control ventilation. I wanted the chicken coop door to be on the floor of the raised coop so the wind wouldn’t blow in. I also installed a roof vent rather than a wall vent, although I do have a small wall vent that I close in the winter months. Otherwise, there is too much ventilation when the cold winter winds blow and it also allows snow to get inside the coop. The second idea was to position the coop in such a way as to maximize the sunlight that would come through the windows during the winter months. This would add a little bit of heat to the inside of the coop. Third, the roosting bar inside the coop was made out of a 2×4. The reason for this is, chickens have a hard time wrapping their toes around objects unlike other birds. If they can perch flatfooted, they can lay on their own feet and toes keeping them warm.
The fact chickens are built to survive the cold is surprising to some, but the reasons are really quite simple. Chickens’ bodies generate a lot of heat, and their feathers act as insulators trapping that heat. When it’s cold out, chickens will fluff their feathers out, creating small pockets of air. As their bodies heat the pocket of air, it remains trapped against their body keeping them warm (much like the fiberglass insulation in your attic). As long as the wind doesn’t disturb the feathers or the warm pockets of air, they will remain warm, even on the really cold days. Still yet, chickens have a layer of down beneath their feathers for added warmth. To keep their toes from freezing, they will lay on them much like they would an egg. If you look at the picture to the left, you can see how these chickens cannot wrap their toes around the round perch bar (the ends of their toes aren’t touching the bar). This makes it difficult for them to keep their toes warm because they can’t easily sit on them, leaving them exposed to the cold air. This is why we used a flat 2×4 cedar board.
So how cold can it get before they start having problems?
Our adult chickens have had no problems, all the way down to -10°F throughout the night. I have to admit, I was a bit worried and checked on them the first few times, but they seemed just fine sleeping on their perch inside the chicken coop. I don’t worry anymore, even when a winter storm with 60 mph winds came barreling through. Again, as long as the chicken coop protects them from the wind, rain and snow, they can withstand quite a bit. I’d probably get worried again it if got down to -20°F, but that hasn’t happened yet.
As an added note, putting a heater in the coop is not a good idea. There are many stories and pictures on-line where coops have burnt down due to the chickens knocking over the heat lamp whereby a fire ensued. I have also read that once a chicken adapts to the cold, suddenly heating the coop can shock their bodies because it gets to be too warm. Or, if they have always had heat and if for some reason the heater fails, the chickens will again be shocked, but this time by the cold. The chickens need to adapt to their winter and summer environments slowly, over a period or weeks or months. The only time I would put a heater in the coop is if on an extremely cold night, the chickens looked like they were stressed. And even then, I would only heat the coop to where the temperature was just enough to not stress them out. For example: if there was a really cold night where it got to -30°F and the chickens were stressed, I would only heat the coop back to -10°F or 0°F.