I have 14 chicks. When they go outside I want them to have a fenced in yard. At first I didn't think I needed to fence in the top. But last week a friend of mine, who has had chickens for years, had a preditor climb over the fence into her coop. What ever it was, it killed her rooster and the brooding hen! So I dont want this to happen to my babies. Now I need to figure out how big their run needs to be. (Before I was going to have it very large because it was going to be open at the top.) Any suggestions?