I'm planning a chicken run with an overhead roof of chicken wire and have lots of questions. I'm dreaming of a run that is 24 x 24 with the coop enclosed in that area. How close together do the upright posts need to be? Do interior posts have to be 4 x 4 also? How close together do I need to set the overhead ties? Do the overhead ties need to be 2 x 4? What is the best way to attach the overhead ties? Any advice you can give is appreciated.