Torrens Building Adelaide,
Photo by Bahudhara,
CC BY-SA 3.0,
via Wikimedia Commons
A web search found the Carnegie Mellon University Australia is also located in the Torrens Building, as is Torrens University Australia. All three of these institutions feature photos of the Torrens Building on their websites. Both UCL and CMU have photos of the building, each with only their own flag out the front. CMU Australia also show photos of teaching facilities and a video.
It is not clear if each institution has its own teaching facilities in the building, or are sharing them. Having shared facilities would be good for the students, but would be a little misleading if each institution to fails to mention that and so implies they have the building to themselves.
Of course, universities are not the only ones which recycle buildings in this way. The Australian government has an impressive looking military command centre, which appears in the media with different names and functions attached to it.