We brood ours inside for three weeks. We usually get them very early in the spring. VERY early. Lol. Like late Feb, early March. During those three weeks we use puppy pee pads, changed every evening, and there is no dust. At the end of three weeks they go outside into a Rubbermaid storage shed, mostly kept closed except that we open the top during the day unless it's raining. As someone said, they huddle if they get cold. At about five weeks we open the doors during the day and let them explore the world unless it's wet, snowing or really cold. They share a fence with the big girls so at eight weeks we open the gate that separates them and integrate them with the adults. Basically we only wait that long to keep them safe from the cats who might otherwise think, Oh yum! Baby birds!