NOW y'all are getting it!
I have 6 week old chicks, and they are not fully feathered on their backs. They LOOK fully feathered, but if you look under their wings they only have fuzz. These are staying in the garage until 8 weeks. Now, my 8 week old chick IS fully feathered, and so in a couple of weeks all of the chicks will be turned out to the coop. Yes, even at the temps we have. Since the coop is insulated and draft free, they should be fine. I just keep an eye on them, and look for signs of stress and pull them back inside if they seem to be too cold.
We are definitely affected more by the low temps and the wind than the chickens are. Heck, I have to watch out for frostbite more than they do!
As for the waterers, my chukars are all outside, no heat - just a box with straw to huddle in if it's too cold - and a rubber water dish. I save my old 1 gallon milk jugs for water, and take warm water out to them 2-3 times a day. I just turn the bowl over and step on it lightly to crack the ice out and refill.
In the breeders coop we have heat tape on the watering system (drinking cups) and that keeps the line from freezing. First thing in the morning, if they've left any water in the cups, that will be frozen. But once I pop out the ice, they work all day. The rest of the coop is insulated and draft free, but not heated. The bottom line? Everyone is fine, even my quail.
*edited because I can't spell this early in the morning!...
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