When is appropriate to move my 11 week old chicks outside to the big coop? The chicks are already fully feathered and are getting pretty big for the brooder, so I would like to move them out as soon as possible. There are 10 of them. I don't think aggression with the other chickens will be an issue since there are so many of them, and they are almost as big as the other chickens. My only worry is really the cold. It is starting to get cold here(Northern New Jersey). We are experiencing temperatures down into the 30's at night. I don't want to over rush them into the big coop, but I also want to get them out of the brooder and get outside in the fresh air.