I have 8 large breed chickens but I'm afraid that I may have built my coop to small. The coop dimensions are 4' wide by 4' deep, 5' high front and 4.5' high back. Currently the girls are only 8 weeks old and are loving there home. I'm afraid that they are going to run out of space though. Should I give them an addition or will they be fine? Winter is coming quick and I would rather not have to work on it when it gets cold. Any advice would be greatly appreciated.