My 4 hens are in a 4 x 2.5 ft coop with a ramp out to an enclosed 4x8 run. Nightime temps are already down in the 20's. So far I have added a 40 watt red lamp to their coop but I am nervous they will peck at it as it is within reach when they are roosting. The metal watering can is in the run and sits on top of a hollow cinder block with a low watt bulb inside to keep the water from freezing. Both the coop heat lamp and the bulb under the water are on a thermostat to come on at 35 degrees and shut off at 45. I plan on leaving the coop door open so the birds can go in and out at will. The coop is not insulated but wind free. Anyone have more or better suggestions? It will reach zero sometimes this winter. Thanks!