Minimal recommendation is for 4 s.f. in coop and 10 s.f. in run per bird. Any less than that sets your flock up for behavioral, stress induced issues including illness, aggression which can lead up to cannibalism. By the time a chick is 2 - 3 weeks old, she should have 2 s.f./bird in the brooder. Nest boxes: 1 box/4 birds.