Hubby and I are making a coop out of scrapt wood that we found on craigslist and freecycle. The question is: How big of a coop do we need to build for Max amount of 40 chickens? We live in Florida which means storms and hurricanes so we want to build a coop that is big enough for the chickens to stay in during our bad storms which could last a few days. What size would be comfortable for them?