I'm in Southern Quebec. The thermometer in my car said -29 this morning when I got in (Cel...but at that temp, Far. and Cel are pretty much the same). Ours are out locked in the coop. Make sure they have plenty of food, add some scratch and/or suet if you've got it. We have a pretty eclectic mix of chickens...but almost all winter hardy breeds (Dominiques, Chanteclers, Easter Eggers, Ameracaunas, Cochins...and a couple Polish...possibly my only NOT so hardy breed). They were cold...but fine. I've not seen any MAJOR frostbite, either.