I'm in Alaska and don't heat mine, lots of insulation r19 and visqueen, have 2 halogen lights on 6am til 9 pm and have been getting 2-3 doz eggs per day all winter, about 40 hens. When it gets down past -20, I do use one heat light. Coop is 8x12, and I leave chicken door open all the time H20 is always outside.
I live in norther ontario my coop is insolated really well i donèt use heat lamps or anything and i acually had to cut a hole to let the heat out a bit cause it was getting damp and freezeing
i live in Maine i dont insulate my coop they do fine in the maine winters i have 10x12 gambrel mini barn for my coop. i have sex links. gl wyandottes , barred rocks. delawares,
I don't yet... but I'm in the Sudbury area, and plan on building a shed/coop with insulated walls and lots of ventilation. I am planning to use as little electricity as possible, so I'll be incorporating south-facing windows for solar gain, and will be experimenting with a homemade solar water heater to keep the drinking water warm (which will add a bit of heat to the coop).
Mine is not insulated..I have the light on 1 hour in the am and 2 hours in pm, door open most times. Except this last weekend at -30 with wind chill I closed the chicken door most of the day. Still getting 15 eggs a day out of 20 hens. Chickens adjust to the weather. They even go outside sometimes.
First, disclaimer, mine is not a typical small-backyard-coop situation. Also I am only an hour N of TO -- we regularly get down to -30 C and occasionally below, but it ain't Northern Ontario
That said, my chickens are in a 15x40 building with insulated 6" stud walls and a well-insulated ceiling, on a slab that stores a lot of heat from the summer and transmits heat from belowground. It is basically unheated -- the last 2 years I have plastic-wrapped a 4x7' lean-to style run on the S side that acts as a popcan-style solar heater and provides some noticeable benefit on sunny days, but even before I started doing that, the building did not get below about -8 or -10 C during the winter. This is with the popdoors open most days (not the nastiest, and not always *all* day) but with no other ventilation open besides the popdoors (possible through good hygeine and the fact that I have only a couple dozen chickens in this very large building - Do Not Try It in a more normally-populated coop!). Actually this winter I do not believe it's been below about -4 C, and only temporarily that low. Currently it is about 0 C in there, would be about 5 degrees C warmer if the sun were out (what's with all these cloudy days? hmph)
So that is another approach. Large very well-insulated building with large thermal mass. Solar heating helps too, esp. insofar as you can capture that heat into thermal mass to tide you over the nights.
I will be building an open-fronted coop off the back of my horse shed this summer, for chanteclers that I want to try free-ranging in the horse pasture. I do not *anticipate* problems with them with the low temperatures even though I expect their coop will get down close to ambient outdoor low temps... but, who knows, we shall see.
I think the size of the flock helps. If you've got 20+ chickens, they can keep each other warm. I wouldn't do a small flock in an unheated coop and extreme low temps.
