This past June the St. Louis Central Library designed by Cass Gilbert closed for a $79 million dollar renovation which is scheduled to be complete for the building's 100th birthday in 2012. The renovation will restore historic ceilings that were altered to install fluorescent and recessed can lighting, provide new HVAC and plumbing systems, introduce a new auditorium as well as several other improved spaces.
The week before it closed I took a brief tour of the spaces beyond the bronze doorway at central desk of the great hall. Here was housed the central stacks that while generally closed to the public contained a structural system making it possibly one of the more interesting features of the building.
Upon entering the stacks you immediately experience that made this off-limits area so interesting, the glass floors! The glass floors were designed to let natural light from the exterior windows filter deep into the rows of shelves. According to library history, when originally built the stacks had one light bulb for every other row of shelves, which meant that making every allowance for day-lighting was of great importance.
An engineering feat themselves, the stack shelves rise the full 7 levels of the stack tower and support the glass and steel floors at each level.
While unique to St. Louis, the Central Library's system of glass floored stacks was used in many larger municipal and university libraries in the late 19th and early 20th centuries.
The fluorescent lights near the exterior wall are left off during the day as daylight fills the aisles.
Unfortunately with the Central Library's renovation this intriguing feature will be removed to open up the former stack space for a new atrium and entrance facing Locust Street. The library already has two original accessible grade level entrances on Locust Street, so why a third is needed is to me beyond comprehension.
Those who argued for eliminating the old stack tower say that the stack tower was a fire hazard. While the design of the stack tower with openings between floors could be an issue, any time you have a high density concentration of books, you have a potential fire hazard. Employment of modern fire suppression systems are the safest and best way to prevent devastating fires.
Another feature of the Central Library that will disappear with the stacks is the pneumatic tube system.
Requests for books were presented at the central desk in the great hall and sent via the pneumatic tubes to the stacks where librarians retrieved the books and brought them to the patron at the desk.
I can understand that this system requires more employees to keep running and that there are probably other benefits to an open stack system, but having someone else find your book was pretty nice. Librarians: please weigh-in.
These dumbwaiters were used to ferry piles of books back to their appropriate level for re-shelving upon return. They will also be removed with the stack tower.
Below is a video from KETC Channel 9's Living St. Louis series that gives a good synopsis of the Central Library's history and features.
Near the end of the video are a sequence of historic photographs showing the construction of the seven story stacks and glass floors. If you could play this in reverse you can imagine how the demolition crews equipped with cutting torches will soon disassemble the stack tower, cutting the steel into pieces, tossing the glass into a dumpster and destroying this unique structure (for St. Louis) forever.