I am thinking about buying 20 straight run white rocks, keeping the females for eggs and butchering the roosters (except for one, maybe 2) and I need some ideas. I want to be able to leave the pullets in there as layers, planning to butcher the roos at 12 or 14 weeks (I'm not sure how they compare to the cornish crosses, I need to do more research on that...)? What dimensions do I need? How high does it need to be for the chickens only, I don't need to be able to stand inside it. Is 2' high enough for the run? (they would be able to free range quite often, the run is really just a back up for the days they can't free range) And I was thinking 3' or 4' for the housed part that will contain the nestboxes and roosts. I need something fairly simple, I don't have a lot of building experience. Thanks in advance!