Well, watching the mercury fall, fall, fall today, I decided to be more proactive in keeping the girls comfortable. Today, I turned on the heat lamp we installed in the coop when it was finished, something I didn't turn on once last winter for fear of overheating them. We turned it on this morning and watched the coop temperature rise to 26 degrees by 4pm. The hens turned in and I turned off the heat and shut the pop door. I believe there's adequate ventilation, we're hovering at about 42% humidity in the coop with an outside of 71%. 30 minutes later and it's only dropped one degree. We're forecast to get to -4 tonight. It's 6 right now. I sure hope I can keep it in double digits through the night. I wouldn't be so worried but they're still molting. Not a hard molt at all, there's no skin showing. But their wattles are paler than usual and their energy level is reduced and their food intake is less. They sure liked the warm scrambled eggs I brought out midafternoon, tho! Wish me luck!