We have 16 one to two week old chicks, and have a coop to build. We had originally planned to have..well...8. And now we have 16. I am learning that this is a common occurrance (at least we didn't already build the coop - that would be a bit of a disaster!!) So we need to double the size of our intended coop. I want it to be movable, since eventually we want to have the chickens help us out with rotational grazing. Our original plans were for a 4x8 tractor, raised 2 feet off the ground, with food and water underneath, and a fenced, covered, detachable (for moving) run, plus we will likely free-range for at least part of the day when they get older. We live in a fairly warm climate - it rarely even gets to freezing here, and it never, ever snows, but regularly is over 100 degrees in the summer. The original plan was to make a double-sized Purina Mills style coop, but due to our warm summers, I was thinking that I'd only enclose 3 sides, and have one of the long sides just be hardware wire, and possibly have one of the shorter sides able to be taken off (with hardware wire underneath) in the summer. I'd have a tarp available to close off the open side in the event of a really wild winter storm, I guess, since I wouldn't want soaked chickens and bedding. If I raise what would have been the main floor of the coop to 3 feet off the ground, and enclose the bottom level the same as the top, and add in a ramp to the second floor, would that give me my extra square footage? Would I need another plywood floor for the bottom, or could the ground act as the floor of my lower level? We are on 5 acres, so it really wouldn't be any problem at all to dump shavings on the ground under the coop as we move it around. We would just rake up yucky litter and carry it to the compost whenever we moved the coop, or, depending on where it was, just let it compost in place. FWIW, from what I've seen of friends chickens in the area, they are outside even when it's rainy here. Most people seem to do more like 2 sq ft of inside coop space per chicken (all the 2x3 ft coops claim to fit 3 chickens). They probably get away with it because just about everyone also either free-ranges or has a roomy run that gets used year-round. I guess it just doesn't get cold enough to keep them in. My guess is that even in incliment weather they will make full use of at least the entire covered portion of the run. Do you think I'd be ok with the two story desgin? I don't want anyone over-crowded.