I just finished my coop and put the girls out a few days ago. They are 6 weeks old. The coop is completely enclosed by 1/2 hardware cloth. Today I noticed a neighborhood cat sitting on top of the fence eyeing the chickens. That was in the morning and he was back in the afternoon. I seem to remember reading that generally cats are not an issue to worry about. Is that true? We live in the suburbs so there are plenty of house cats strolling around the neighborhood. Check my BYC page so you can see my setup.