We've got 25 chickens we plan on free-ranging. They'll be roaming from after breakfast to dusk daily once they're adults. They're currently 4 weeks. We've been advised to keep them fully confined into their coop and run until they are full grown adults, because there are other free-range hens and roosters in the neighborhood. We just finished the coop, and DH is going to get the fencing for the run tonight. The problem is that I don't know how big to make the run! The only time we plan to confine them is during the day in inclement weather. How many square feet should be allowed per bird in the run for that condition?