Our chickens will be free range 98% of the time on our 12 acre property inside of a 1 acre yard. But it can rain a lot here in East-Central Texas. I was wanting to build a covered run for them for rainy days to stretch their legs. We have 12 chickens but only 6-8 of them will be using this run at a time(the others already have a prefab coop/run combo). How big should this new run be if they will only need it for two days or so at a time? They will still have access to the rest of the yard. I just want a covered run next to their coop should they decide to hang out under it. Thanks!