I've talked before about my current office space. It's cool that it's in an old O'Neil Ford building but it's not-so-cool in that the public spaces of the building haven't been particularly well maintained. Mismatched lights, dated paint colors and stained carpet all create an aesthetic that doesn't say "creative professional" so much as it communicates "creepy".
This is something the owners of the building have recognized and are currently working to correct. In addition to updating the restrooms so that they are more accessible and smell less like pee they are also upgrading the finishes of the corridors. There's only so much they can do with these spaces due to their low ceiling heights: raising the ceilings isn't really an option due to all the services that - up until a few days ago - were run in the plenum space above the acoustical ceiling that has been temporarily removed.
The "plenum space" of a building refers to the cavity between a ceiling and the roof or floor structure above it. This void is used to run the HVAC ducts that feed conditioned air throughout the building. All the remaining space then acts as a big return air duct that recirculates air back to the air handlers. Of course all this extra hidden space above the ceiling also provides a place for wiring to be added. For an older building that has been modified to fulfill a new purpose like the one I am currently occupying there ends up being a lot of stuff stuffed up above the ceiling (see above). Between multiple telephone lines, various cabling by multiple internet providers and additional power feeds, the plenum space ends up being a solid mass of wires, ducts and perhaps a rodent or two.
But even in this extreme state the plenum space is demonstrating its value. By acting as a relief valve for new technology, the plenum space allows a building to adapt to new uses and technologies. What goes on above the ceiling might not be pretty, but it is very important.