I already had 20 grown chickens . I decided to enlarge my flock by adding another 30 chicks. I need to build another coop and was wondering just how large a coop do I need to build now to house such a large flock. I still have the chicks separated from the main flock , but it want be long before they are ready to join the others. The coop I have now is 8 x 8 . I was planning on building another 3 times that size.Possibly building it 24 x 16 or 24 x 24. I already have a run for them and also free range my birds. They love it.