I’m in Northwestern Wyoming not too far from Yellowstone Park. We’ve been known to get snow in June. And we get cold - sometimes 2 weeks in a row where we never get above 10 to 30 below zero with winds that can hit 50-60 mph and sideways falling snow. (Why do I LIVE here?

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My coop is neither heated nor insulated. Even my Silkies did great as long as they were allowed to acclimate slowly and naturally to falling temps and short days. When we did chores, we left the coop door open. If they wanted to go out in the snow, they simply did. I had a mixed flock of Bantams, Standards, and of course the Silkies, all living together and they didn’t mind being outside. I have photos of my Silkies out in the snow when it was only 9 degrees.
If you want to add a little heat to keep water from freezing, there are all kinds of ways to do that from cookie tin heaters to small, plastic rated stock tank heaters in a bucket, which is what we did.
There are two keys here - the first is to remember is that you’re there, I’m not. So a lot depends on your own personal comfort zone. I’m much more relaxed about chicken raising than most folks - I don’t stress and they do great. I even raise chicks outside in springtime temps that are in the 20s, sometimes dipping into the teens, without a heat lamp. That’s my comfort zone for raising them and Mama Heating Pad provides all they need. The other key is to allow them to gradually acclimate. Going from a 70 degree house with a heat lamp to winter-like temperatures with nothing is risky. I did it with 5.5 week old chicks, it worked perfectly for me, but I’m smarter now. Now since mine never have a lamp or heat lamp, I don’t have that transition.
So look over all the options and choose what you think will work for you and your flock. Disclaimer: I’m on a one-woman crusade to rid the chicken world of heat lamps.