I think people underestimate the power of a chicken. I use no heat lamps etc. My birds have wind breaks but many perch out side in the weather year round. I don't know why when they have a choice, but they do. Here in Iowa we have had many days -30 or better and thats with out wind chill. The birds just take it and do well. Some of the things I do keep in mind is they need fat and I don't mean from corn. I mean from fat, meat, the bugs they are not getting in frozen weather. I have friends that hunt and bring me allot of deer. So I used the pieces of scrap, fat etc and freeze what they won't eat that day for later feedings. I lay out the hide and they pick it clean. When I don't have deer fat I ask the butcher for fat, yes it costs but not as much as replacing my flocks. All my friends know that I gladly will come pick up buckets of gutts and what ever they would toss out when butchering as well. Its nasty, yes, but my birds are fat even at the end of winter. I think feed is more important then shelter and heat lamps personally. I don't worry about water with snow on the ground either. They drink so little due to eating snow that I stopped watering years ago when there was snow on the ground. This goes for my rabbits and cattle as well. I learned that they really don't do more then take a sip, and leave, so why bother? My animals are actually healthier for it. I had a hard time mentally the first year I experimented with it, however the more I offered water and the more they refused the more I realized that nature was doing something here, and I was better off to let it.
