Here's my coop. It was built for my comfort as much as theirs.
https://www.backyardchickens.com/web/viewblog.php?id=167-Minnesota_Coop
You certainly don't need anything fancy. Chickens can survive extreme cold with a good sturdy shelter.
The biggest problem in the middle of winter is water. That's the main reason I have heat in the coop. I hate filling buckets and using hoses in winter.
keeping the coop just above freezing eliminates ice and makes me very happy!

https://www.backyardchickens.com/web/viewblog.php?id=167-Minnesota_Coop
You certainly don't need anything fancy. Chickens can survive extreme cold with a good sturdy shelter.
The biggest problem in the middle of winter is water. That's the main reason I have heat in the coop. I hate filling buckets and using hoses in winter.

