I live just south of you in TN just south of the KY state line so we share similar weather and I don't do any thing as far as heating the coop. Like others have said it's really about good ventilation. I've sometimes wondered if our chooks don't have it a little worse than some that are located farther north just because it's not greatly unusual for it to be 65 degrees on say a Tuesday afternoon and then by Thursday night it may well be 8 degrees over night
. And like you I have worried that those single digit temps would be too much cold for the chickens but this is my third year w/ chickens and they always seem to do fine and I have had zero issues with frostbite. Now I do have heated waterers but that's more for my peace of mind to know that they have access to the fresh water and food that they need in winter. Anyhoo very best of luck with your chooks and I hope you find a plan that works well for you
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