Our 12 Rhode-Island red chicks are doing great so far! We've had them two weeks (got them at one day old). They are growing so fast! When I let them out of the brooder in a couple weeks, I have to figure out where to keep them as I want them to be around the grown hens but not to be attacked - I can't let them run free during the day with the hens, can I? Not until they are several months old, right? This is only my second batch of chicks. I got the other ones two years ago and they had the coop to themselves, now the new ones will eventually have to get integrated in. They (hens) run free during the day and are locked into the coop with roosts at night. The brooder with the chicks is in the coop. The hens use nest boxes in the coop during the day. The coop is big, about 15' x 20'. I can partition a part off for the chicks initially - is that what I should do when I let them out of the brooder?
They are much too small compared to your full grown hens. You can definitely partition them off from each other so that they can still see each other, then when the younger ones are quite big, maybe around 16-18 weeks or so, you can try integration by letting them free range together.