A beloved Seattle landmark looks ahead to its next 50 years
Not long after Olson Kundig was hired for the renovation of Seattle’s iconic Space Needle, I had the opportunity to explore behind-the-scenes portions of the building with Alan Maskin, the project’s Design Principal. It was our first chance to study the existing interior and exterior conditions of the tower; we started from the top of the roof antennae platform and worked our way down to the revolving floor of the restaurant. To observe the cavity below the floor, we descended through an access hatch and crawled across HVAC conduit, plumbing lines and structural members.
Cover image: © Hufton + Crow
We were drawn to a ray of light piercing the darkness of the space, a baseball-sized hole in one of the floor panels. For a moment, Alan and I forgot we were crawling on deteriorating, soon-to-be-replaced metal decking 500 feet in the air. We sped to the hole and peered down.
It was breathtaking.
Through the hole we could look down on the elegant legs of the Space Needle stretching to the ground and watch the elevators raise and lower, shuttling visitors along the 500-foot length of the tower. We’d seen a similar view in historic photos, captured by local photographers during construction in the early 1960s, before the exterior façade was installed. But seeing it in person was incomparable.
Those early photos didn’t capture the incredible thrill of the sight before us; we were enthralled. The hole was just large enough for my camera lens, and I took a picture to share with our team back in the studio. Alan and I took turns looking through the hole until we remembered we were laying on a panel already rusted through. We shared a nervous laugh and cautiously backed away.
That experience – a new perspective on a familiar landmark, the full-body thrill of vertigo – would come to be our guiding star through the work that followed.
The Century Project
Originally built for the 1962 World’s Fair, the Space Needle remains an iconic, internationally recognized feature of Seattle’s skyline. Around the tower’s fiftieth anniversary, visitor surveys revealed that the experience wasn’t matching up with expectations. The Century Project, a renovation that aimed to position the tower for its next fifty years, sought to recapture the original thrill that visitors felt when they first stepped off the Space Needle’s elevators in 1962 and saw breathtaking views of Seattle and the surrounding landscape.
In many respects, our design approach was more subtractive than additive, peeling away the many decades of additions and modifications that deviated from the purity of the original design. The original building was a monument to an era of technological optimism. Its renovation offered the opportunity to renew that sense of optimism, while better reflecting Seattle’s technological prowess and know-how.
The challenge for us was to identify and edit the elements that obscured or limited the expansive views of the constantly changing city below.
The solution was 176 tons of glass.
Open-Air Observation
The renovated Space Needle incorporates 196% more glazing throughout the upper levels of the tower (known as the “top house”). This is especially impactful on the Observation Deck, where visitors first experience the thrill of the redesigned tower and incredible views across the city of Seattle. From the moment the elevator doors open, a new 360-degree wrap of full-height glass is revealed. Throughout this level, interior barriers and low walls have been removed – widening views by 65%.
The added glass has the benefit of democratizing access to that incredible panorama, replacing obstructions that kept visitors in wheelchairs or children in strollers from seeing out and sharing in the experience. As father to two young children – who have now visited the Space Needle many, many times – I know first-hand how enthralling the view can be, especially for children. It’s deeply satisfying to know that the view is now more universally accessible.
Outside, metal security cages and solid walls have been replaced by 11-foot, 7-inch panels of glass. Angled outward at 14.5 degrees, the glass showcases advances in building technology since 1962. The only thing separating visitors from unobstructed views is a transparent barrier made of three, 15-millimeter panes of ultra-clear, low-iron glass, with two 2.28-millimeter SentryGlas® (from Trosifol/Kuraray) interlayers that provide structural strength without sacrificing clarity.
A sequence of 24 integrated glass benches along the perimeter act as perches for visitors. The benches are high and angled toward the open air – sitting, your feet dangle above the floor. It creates a deeply engaging environment rarely seen in architecture, where people use their whole bodies to experience the building – they sit, stand or even lay down, leaning over the edge of the deck, the city hundreds of feet below.
From Hole in the Floor to Oculus Stair
Previously, guest access between the upper and lower levels of the top house was limited to the elevators or a cramped stair. The renovation inserted a wide, airy central staircase, circulation reimagined as sculpture. The new stair, made of steel, glass and warm wood, celebrates the connections between levels and adds to the sequence of views from the tower. As it gently curves between floors, the stair preserves space for a new window at its base – inspired by that early view through the rusted floor panel.
The Oculus Stair continues the design ethos introduced at the Observation Deck, removing obstructions to make the original structure more legible to visitors. In doing so, it provides a new method for understanding the Space Needle, showcasing the sweeping lines of the tower’s legs and the cheerful gold elevators that travel its length hundreds of times each day. Like the exterior panels upstairs, the curved oculus is made of many layers of glass, creating a surface visitors can walk, stand, lay or sit on.
The World’s First Rotating Glass Floor
Arguably the most dramatic addition is a few steps away from the oculus: the world’s first rotating glass floor. Known as The Loupe, the transparent floor gives visitors never-before-seen views of the elevators, the mechanical apparatus powering the floor’s rotation and the Space Needle structure itself. Like the glass wall of the Observation Deck, the Loupe’s signature glass floor inspires a full-body interaction with the architecture; on any given day, I’ve seen people tip-toeing gingerly along the seams and fully stretched out on their stomachs, intently watching the world below.
Though it can be scary to step onto the glass floor for the first time, we worked closely with a team of engineers and fabricators to ensure that it only feels risky. The floor includes a 6-millimeter annealed glass “scuff ply” top layer that can be easily replaced if scratched by extensive foot traffic over time. An added layer of security film on the underside cushions lower layers of glass and, in the event of damage, contains any loose glass fragments. Below the “scuff ply,” three, 10-millimeter plies of heat-strengthened glass laminated with two, 2.28-millimeter SentryGlas® ionoplast interlayer create the floor’s structural deck. This stack also forms the upper half of insulating glass units with low-E coating that act as the thermal boundary between the interior and service space. To further improve thermal performance, an additional layer of low-E coating was added to the underside of the floor.
Views From Below
As a historic building and protected landmark, the Space Needle was subject to a rigorous design review process, including oversight from the local Landmarks Preservation Board. Their approval of the design was contingent on not altering the tower’s original look and profile, so the new glass floor had to appear opaque from the exterior, just like the original metal decking being replaced. The challenge became how to make the glass floor transparent in one direction and opaque in another.
We modeled and tested a variety of approaches, ultimately using glass with a soft grey frit pattern applied to the underside of the floor, similar to wraps used for advertisements on city buses. The frit pattern density is fine enough to be imperceptible from the interior, as higher levels of light from the outside causes the human eye to focus on the exterior environment. Conversely, lowering the light levels inside the Needle causes viewers’ eyes to naturally stop at the exterior face of the glass. Although the interior visitor experience is dramatically altered, from the ground below it’s almost impossible to tell that anything’s changed.
Additional Considerations
Glass is a familiar material, but deeply complex. Our decision to incorporate so much glass drove the technical work forward on many other fronts. We studied the effect of wind on the new glass barrier, from the increase of the building’s lateral load to how the wind patterns would affect the ability to open or close the exterior doors to the observation deck. We analyzed the added heat gain from the additional transparency, which in turn informed decisions about HVAC systems. And, of course, we worked with Richard Green, who led a team including Front Inc, Magnusson Klemencic Associates and Herzog Glass, to test our ideas, build mock-ups and generate extremely robust project drawings.
Getting all of that glass – 176 tons, with individual panels weighing up to 2,300 pounds – to the top house posed its own challenges. While some pieces could be brought to the worksite in the elevator, others – including the Oculus Stair panels – were too large to transport there. In one of my favorite examples of worksite innovation, Hoffman Construction, the project general contractor, devised a system in which drone engines were attached to the oversized panels. As the panels were craned to the top of the tower, the engines could be controlled remotely to steer the glass, keeping the panels from swinging and hitting the tower legs. Once they arrived, a specialized glass-setting machine – developed specifically for this project – hung over the side of the tower and kept them in the correct position for installation.
A View of the Future
Just as the original tower did in 1962, the renovated Space Needle celebrates the creativity and innovation that characterizes our region. The tower includes some of the most exciting modern advancements in design craft, materials science, seismic engineering and building technology, incorporated in both obvious and unseen ways. It’s a case study for the impact of collaboration, as well as an exercise in optimism and – for a city that feels a deep sense of personal ownership over the Needle – incredible trust.
The view from the Space Needle offers such transformative potential. In fact, local historians believe that giving people an elevated view of the city in the 1960s actually impacted on Seattle’s growth, urban development patterns and regional connectivity.
But the personal impact is more immediate. The first time I took my daughters to the newly renovated Space Needle, my youngest – about 2 years old at the time – went straight to the rotating glass floor, laid down and looked straight down to the ground below. Toddlers aren’t known for stillness, but there she was, motionless and engrossed, for easily 15 minutes. She was completely mesmerized by the view – just as Alan and I had been several years before, peering through a hole in the floor.
This article was originally published in IGS Magazine’s Autumn 2021 Issue – Glass Retrospective: Read the full Magazine here for more thought-leadership from those spearheading the industry
Author: BLAIR PAYSON, AIA, LEED® AP Project Architect for The Century Project at the Space Needle and Principal, Olson Kundig
Blair Payson joined Olson Kundig in 2004 and has worked on both architectural and exhibit design projects, including the Century Project for the Space Needle, the Bill & Melinda Gates Foundation Discovery Center and [storefront] Olson Kundig, as well as several residential projects across the Western United States and Mexico. A maker at heart, Blair is an architect who revels in the details. From large cultural projects to temporary design interventions, Blair is able to distill large, complex projects into distinct culminating moments.
Lately, Blair’s research has taken him on-site visits to a subterranean cavern deep underground in one week, to hundreds of feet above an urban landscape the next. This demonstrates not only the range of Blair’s interests, but also his proclivity towards risk and experimentation. Blair holds a Bachelor of Architecture from Rice University, and he is the recipient of several design awards for his work on the Space Needle, Gates Foundation Discovery Center, among other projects.
PROJECT CREDITS
Olson Kundig Project Team: Alan Maskin, Design Principal; Blair Payson, AIA, LEED® AP, Project Architect; Marlene Chen, AIA, LEED® AP, Crystal Coleman, LEED® AP, Alex Fritz, Julia Khorsand, Hayden Robinson and Nathan Boyd, Architectural Staff; Naomi Mason, IIDA, LEED® AP, Interior Design; Laina Navarro, Interior Design Staff
Key Consultants & Project Partners: Seneca Group, Development Manager; Battle Management Consulting, Owner’s Representative; Hoffman Construction, General Contractor; Front, Inc., Glazing Consultant; Magnusson Klemencic Associates, Glazing Engineer of Record, Seismic Improvements Structural Engineer; Fives Lund Engineering, Turntable Engineer; Herzog Glass, Design Assist Glazing Contractor; Arup, Structural Engineer and Mechanical, Electrical and Plumbing Engineer of Record; Holaday-Parks, Inc., Mechanical and Plumbing Design Assist Subconsultant; Holmes, Electrical Assist Subconsultant; Niteo, Lighting Design; RDH, Building Envelope Consultant; Tihany Design, Restaurant and Café Furniture and Finishes Designer; McVey Oakley, Restaurant, Café and Kitchen Architect of Record; BRC, Acoustical Engineer; Karen Braitmayer, Accessibility Consultant; T.A. Kinsman Consulting, Code Consultant; Eric Tuazon, Fire Protection Consultant; O’Brien & Company, LEED Consultant; FS2, Inc., Vertical Transportation