I'm in Alaska...right now it is below freezing. Its actuaLLY 22 degrees right now and its about 2:45 Saturday afternoon. My chicken coop is about 12 x12 for 14 chickens. Their body heat is keeping the coop 50 degrees at nite, therefore... the water is not freezing. I did have water outside but it was pointless as it was a solid block of ice. Moved it inside and viola! my problem has been solved. PS..the entire coop is insulated with 2 inch thick sheets of foam. I have 3 sources of ventilation which include a window, wall vent and little trap door in coop door. All can be open or closed depending on weather.