Maybe a screened window at ground level?
And yeah, I know how you feel about losing your cats outside. Which is why Sterling wears a harness and leash if he feels like going out that badly.
I actually saw a cat leash/harness for the first time ever today, I swear I was like "Wow, what is this" like a kid with new candy. I was tempted to buy it, but I would be the only person around here who is taking a cat for a walk. I need to consider it some more.
I'm more worried about coyotes, and pit bulls, than foxes, though we have plenty. Most of the cats around could give a fox a run for their money. But the coyotes will eat anything, and as I said, the loose pit bulls are nutty, they even tried to attack me. I told their owner if I saw them in my yard again I would take a 2x4 to them. he has already had a couple fines for letting them run loose around kids, and killing cats in peoples yards.
Yeah, that doesn't sound good, luckily there are none near by that I know of, still I would be devestated if something happened to her, she is a part of my family.