How much space should a crate have?

My male boxer, Jefe (11 months old) sleeps in his kennel at night. He LOVES his kennel, because he associates it with special treats and toys. When I'm training his sister, I'll kennel him with a bone to chew for awhile, so he doesn't distract each her. These are really the only times I kennel him.

The kennel came with a divider wall in it so that we could control how much or how little space he had. We started training with a third of the kennel, and he did fine.

However, when we try to add even a little more space (he's grown so much, don't want him to feel smooshed!) he'll pee in it, then cry until we come and take out his blanket he lays on and give him a new blanket. Once we moved the wall back forward so he barely had any room again, he stopped peeing in there.

Even with the limited space, Jefe usually likes being crated. I just feel kinda bad seeing this big strong dog only having a third of his space. I feel like he's going to get cramps or something! He never pees in the house, only in the crate, and only if given more space.

Should I just leave his kennel the way it is, or is there a way to stop him from peeing in it if I give him more space?

Or should I encourage him to sleep outside of it (since he's accident free) and do away with the kennel all together?

How about leaving the door open now that he seems to be housebroken? It can still be his special private place but he can still have room to move should he choose to. I've never crate trained but I think you are doing it right. Once they are housebroken there's really no reason to close the door unless they are still having accidents.

Right, Saje!

Except that I need him to be out of the way when I'm training his sister...otherwise she'd rather wrestle with him than learn how to roll over after a sit-stay. They're so co-dependent that it's nuts! Even when I took him outside right before her training, he was in there for about five minutes before peeing!

I did try leaving the doors on both kennels open for a few days. Guess what? Aside from training, no accidents! Thanks guys. I have been letting him do what he wants at night now though...he's decided that he prefers the couch to his kennel. Hee hee. Who wouldn't?