It doesn't get very cold here in Georgia but the other night as it fell to 12°F (negative with the wind chill, that wind was intense), I went to check on my 6 EEs and I could see that they were visibly uncomfortable. This is my first year of having chickens, their first winter, first coop... so I'm learning a lot. I really had no idea how warm they'd stay but just in case I had the coop packed full, the vents closed a bit to try to keep out the draft, cardboard around the run to keep wind from whipping up inside and around the coop, a tarp over the roof... I was in full panic mode, haha. I tried to put petroleum jelly on their combs/waddles but they were being weird about me putting stuff on them. Figured it was worth a try. They were out of the wind and their coop was dry.
But still, they looked so miserable I went ahead and brought them in. Even my feistiest girl (who'll avoid me picking her up and will pinch me because she's a brat and the boss of the group) huddled into my arms like a big baby when I scooped her out of the coop. Each let me cuddle them as I brought them inside (and really only two of my six are cuddly so that says a lot to me). I like to err on the side of caution myself. It at least eases my anxiety and helps me sleep at night. Plus, I like to save money so usually it's only in the 50s Fahrenheit in my own home so they still get some cold. And it's not too different from the 30s-40s outside usually is.