It depends on which rats you are talking about. Sox & Chops are bitey and fairly destructive. So they get the kitchen table with boxes and stuff. They stay in our office room. So sometimes we let them run around the office floor while we were in the room. Oreo and her sis, Inky (RIP), are/were able to mostly free roam. Oreo is slowing down now and mostly hangs on the living room couch. My boys are too young for the free roaming thing. They must earn the trust. We play with them in the upstairs hall in the early evening. We close the doors and block one set of stairs with plywood (the other stairs we just watch over them). They run all over the place. They pounce on each other and us.
They usually get some individual holding time off/on during the day. They pretty much are spoiled to pieces.
boys: cadoo, cosmo, jinx, moe, ziggy
girlies: sox, chops
gone: Inky--2/7/07 Oreo 4/1/07