I appreciate the info & responses. For the last few nights, I've been bringing their waterer inside our house at night, and in the morning, taking it to them filled w/warm tap water. It had been freezing solid even though it was in the coop. There's a warming trend predicted for week's end...
On another thread someone said that warm water (from the waterer heater) would cause frostbite in the coop b/c warm water evaporates and adds a lot of moisture to the air. Does anyone have experience with heated water putting out a lot of moist air?
Thanks.