I am getting back into chickens after a three year hiatus. I have built two runs and two coops in the past, now I'm starting over again. The best advice I could possibly give: Whatever size you think is large enough, double it. Don't skimp on their run or coop. Don't go with the minimum required space or slightly over minimum, even if you intend to let them out whenever possible. Things happen and you don't get around to letting them out. Happy birds need lots of space everyday to scratch and lay. This time around I'm looking at doing multiple smaller coops that way they will be easier to move around, nothing worse than realizing you need to move a coop that weighs more than a small car. Good luck!