Okay, I have been wanting to have chickens for years and the kids have been asking. I have been noticing that most of the coups are built on a foundation of aggregate and sand as opposed to having the chickens on dirt/grass. Just curios why and where can I learn about that on this site? I live in southern California in an urban medium sized city and only allowed chickens, no roosters. I realize I have much to learn from reading some posts. Looking forward to this!