I'm just wondering what the consensus is...it's 21 degrees F outside, and DH wanted to let the hens out of their coop. The coop has a trap-door sort of opening from the bottom. I just wonder if it is too cold for them to be outside, and if opening the door will let in too much cold air. We do have a heater for their water, and DH has a 60-watt bulb hanging in the coop. Should I keep the bulb on all day? We're 8 months into our fun chicken adventure, and I'll be a lot less ignorant next year! Thank you!!