The so-called “Century Project” nearly doubles the amount of glass coverage on the structure’s flying saucer-shaped Top House, as part of the firm’s efforts to use “subtraction as a guiding design principle,” according to Olson Kundig’s Alan Maskin, the design principal for the renovation.
With this goal in mind, the designers worked to remove the uncoordinated detritus left over from previous designs, including the obtrusive aluminum pony walls separating the indoor observation deck from the open-air viewing area. The effort is geared not only toward opening up the Top House to pristine, 360-degree views, but also toward adding elements that were originally intended for the structure but ultimately were not realized.
The Space Needle debuted in 1962 with one of the world’s first revolving-floor restaurants, ushering in what would become a global trend in mid-20th-century design. The original opaque revolving floor has been replaced with sheets of tempered structural glass fabricated in Germany by Thiele Glas, an upgrade that provides views straight down to the ground below. The glass floor also allows visitors to peer into the inner workings of the Space Needle itself by highlighting the moving gears and pulleys—something akin to a “huge Swiss watch,” according to Maskin—that bring the rotating floor and elevators to life. Engineering services provided by Arup, Fives Lund, and Magnusson Klemencic Associates were instrumental in the design’s precision-driven focus, which included seismic retrofitting and other tricky structural upgrades.
Front Inc. acted as the glazing consultant to Olson Kundig For the duration of the project and collaborated with MKA to engineer the structural glass assemblies for Hoffman Construction, the project’s general contractor.
Achieving Americans with Disabilities Act (ADA) compliance was another key concern for the renovations. The Seattle Space Needle opened 28 years before ADA regulations took effect and contained areas that were only partially accessible to disabled visitors. With the Century Project, the design team brings full accessibility to the Top House by adding a new central “Oculus Stair” that features dynamic treads that collapse into a platform that can carry individuals between levels as needed. In the observation areas, non-continuous glass benches leave ample room for someone who uses a wheelchair to get right up to the outwardly canted glass barriers that wrap the space. Here, the architects have restored visitors’ ability to peer down over the edge of the saucer, an aspect that was lost with the addition of cumbersome safety gear many years before.
The 11-by-7-foot, 2.5-inch-thick glass panels that wrap the observation platform were installed by specially designed robots created by Breedt Production Tooling & Design. The installation, like many other aspects of the renovation, involved navigating “wickedly complex logistics” and a nearly ’round-the-clock schedule. Hurdles for the project included accounting for significant wind deflection in the design and fabrication specifications for many components and designing nearly all components so that they could be transported up the Space Needle’s passenger elevators.
Several feats of design and engineering later, the Space Needle’s new views are crystal clear and fully on display for all to see.