the only thing chickens do not need heat. what they need is a dry draft free house. its the moisture in the air that causes the problems not the cold. I have 8 different coops. 2 poly-dome calf hutches, a concrete block milk house, a barn that is split up and insulated, a duck house no insulation just the holes in the rafters plugged with feed bags, 8x10 shed that is insulated, a contractors shed odd size 10 x 18? insulated bad ventilation, and a lean-to no insulation. the only heat is in the lean-to and the contractors shed. the heat in the lean-to is only to keep the water from freezing and the shed is my chick house so the heat emitters that warm the chicks heats the shed. I get below 0 temps, bad north winds. I have not lost any birds to cold or frost bite unless there is a build up of moisture. last year I lost 0 and no frost bite.