trying to escape?

Last week, Dillon put a hole in my bedroom screen and got out onto the porch roof (2nd floor). He also did it at my girlfriend's where he stayed this weekend, and yesterday, he tore a "portable" screen out of a window (I put 2 screens in the window) that was open about 4 inches. I'm being much more careful now but what can I do besides keep the windows closed? There are no other signs of separation anxiety so maybe it's boredom.
I've been trying to crate train him but he gets very anxious and tries to claw his way out and I don't want him to hurt himself.
I would appreciate any suggestions anyone here may have. Thanks a lot.
Penny

it does sound like sep. anx. to me. can i assume you live on a second floor apartment? could he fall?:eek: . if so, i'd keep the window closed when you're not around. i'd also post in dog behavior and get some library books, check the internet for better advice then i can give. regards, joyce