I don't free range. Too many predators. Since I have both air and ground predators, I have a roofed run, and the anti-dig apron around it. I am glad for both.
The roofed run lets them get out in the winter (some snow blows in, but I have wind&snow break panels on the prevailing wind sides); on...
If chickens are dry and kept out of any breeze strong enough to lift their feathers, they can keep themselves warm. They are wearing down parkas.
I'm in Michigan, so we can get cold, and it can be a raw, wet cold. I have plenty of ventilation in the coop; more than the 1 sf/bird that is the...