I am very worried about fire, so I do not heat. My birds are all in a 100 year old barn, so I am guessing comparable quarters. I just throw extra bedding if we are getting colder weather. Last year I did have a few roosters with frostbite but I was silly and put them in a new spot in the barn and they chose the stupidest spot to roost, above the window where there is a crack for ventilation. Otherwise all survived and last winter we were down to -30 for a week at a time.
