There is an adjacent outdoor exhibit (larger, obviously), but in SF's cool climate the koalas are inside at night and on cooler days. By the way, the size of this box is the same as at San Diego, except they have more boxes for more koalas.
The Cleveland's Zoo has an awesome indoor Koala exhibit, while the outdoor one is rather average. The Koalas are inside most of the time because of Cleveland's freezing weather and their chilly summer nights.
This enclosure in San Francisco is extremely small, and I just saw a koala exhibit at the otherwise excellent Miami Metrozoo that is almost identical in size. Several zoos keep their koalas in tiny, glass-fronted exhibits as perhaps they figure that 20 hours of sleep doesn't require much space...
