Hello, We are new to this site and raising chickens. We have a larger sized hen and 2 bantam chickens. All are 5 weeks old and growing great. We live in Chicago and the weather can get be cold and windy during the winter months. Our question is...Do bantam chickens require a heat source during the cold winter months? If so, what type do you suggest? Thanks. The coop that we have is smaller in size. We were thinking of moving the coop into the garage with a heater. What do you think? Thanks!!