I am in Texas. I feel a little silly worrying about my girls after I read your post. I am new to raising chickens. My girls will be a year in February. They are all Buff Orpintons. I have a little house they go in at night, but they have gotten so big that not all six fit. I covered the little cage part around the house with thick black garbage bags. There is also a roosting bar in that part and 2 of them seem to roost out there all year. This is our first real cold weather in Texas.Freezing tonight! I have a heat light shinning down near the door to the little house, but not inside the house. My entire coop is 12 x 18 and this little store bought house (Tractor Suppy) sits in the center. We actually built another little house, but we can't get them to go in it.It is completely out of wood and we put in stagered roosting bars. They are creatures of habit. They don't like change at all. I read in a book that we need to protect them from the cold because it's all about their comb. We don't want it to get frost bite. I hope I am doing the right thing. We hung something on the north side of the coop yesterday and it blocked the wind really good. Please let me know if you think I need to do more. I did put hay everywhere inside the little house.