Thank you Angie. Yes Lilychick, I have polish in Central Maine...it can get pretty darn cold. My birds are wimpy, once there is snow on the ground they don't like to go outside unless I shovel a "chicken patio" for them. Then put hay down over the shoveled area.
I have never seen them appear cold and I don't have a heated coop. I am careful that I don't use a waterer with a lot of open space, to avoid their wattles getting wet.
Mine are standard polish, I don't know if bantams would withstand the cold the same or not.