I have 3 Barred Rock and 1 Partridge Silkie pullets that are 6 weeks old and are too crowded inside their brooder. I live in south Mississippi, so the winters are pretty mild. The temperatures for the next 10 days will be hihgs between 50 and 70, and the lows between 40 and 55 with one of those nights at 33. My coop is 4' X 6' enclosed and off of the ground. I do have a door on the front that I can close. If I put pine shavings into the coop and a 75 watt light bulb in there, will my girls be OK? I have heard that when you first introduce them to the coop you should lock them in there for a week, so they get used to it and know that is where they need to sleep. Please advise! I am really wanteing them out of the house.