Oh, I should have mentioned that I had them sleep in the brooder in the garage without any light or heat for a few nights before putting them in the coop overnight.
Mine just spent their first night in the coop at about 7 weeks old (they are 8 weeks now), but they could have spent the night a little earlier. Our temps are just a little warmer than where you are. I followed a suggestion on here to put a cardboard box on its side with some shavings in the...