Lots of people will chime in....but I can tell you what I did. I kept my chicks in a brooder in the house until they were 4 weeks old. It was really cold outside (single digits) so I didn't take a chance on moving them outside at those temps. At 4 weeks, I moved them into a dog crate inside the coop. This allowed the adults and babies to be introduced to each other without worrying about the babies being bullied. I let them stay in the dog crate for 2 weeks. At 6 weeks, I opened the dog crate and zip tied some hardware cloth up so the babies could get out but the adults couldn't get in the crate. This allowed the babies to come out and explore but a "safe zone" to go back into if they were being bullied. Luckily, none of my adults bullied them at all. Within a few days of the dog crate being opened, the babies were roosting with the adults at night and accepted as part of the flock. I took the dog crate out this weekend after a week because it isn't needed anymore and just taking up space.