Building an 8x8x8 chicken coop (we affectionately call it the "Coob" because it's a cube coop!). I'm raising the chicks in a brooder right now, but in the future I'd prefer to just let the hens raise the babies for me Should we put the nest boxes near the floor so the chicks can get in and out? Or will I need to separate the broody and babies from the others anyway (which I have no idea how I'm going to do that!)? Also, what is a pop door? How high up should we put the roost? Thanks!