Thanks! I'm lucky to live in Hawaii, if I had to deal with keeping em safe from frostbite and all that it would be a whole other ballgame...
I used to live in WI and now TN. It's really not that hard to avoid frostbite; even with free range. My serama are housed in a homemade solar home (south side of the coop is completely open to sunlight) made of heavy plastic sheeting. Rarely does it get to the freezing point. The hens raise chicks throughout the winter.