We are in the same temperature zone- and we rarely get snow, either. Just lots of cold and ice mostly. Anyway, I think your coop will be fine. I can't see them being locked up for days on end in our zone- I bet you are one zone colder than us, but still. The run looks plenty big enough! If you really wanted more space, you could keep the design exactly as is, and just make the width 4 feet instead of 3 feet. It would add a bit more room, without sacrificing space in your yard. I think this will be a really fun coop! Be sure to post pictures as you build!
