The Space Needle—the iconic “space age” structure that has defined the Seattle skyline since it was built for the 1962 World’s Fair—underwent an extensive renovation project in 2018. This project, led by renowned global design firm Olson Kundig, was officially named the Century Project but referred to by locals as the Needle’s “spacelift.” The $100 million makeover was aimed at transforming the visitor experience at this Seattle landmark for the next 50 years.

To meet this ambitious goal, the design team made significant renovations to the observation tower at the top of the 605-foot Needle that were focused on enhancing transparency. The team replaced walls and barriers in the observation tower, called The Atmos, with floor-to-ceiling structural glass and added tilted open-air glass benches called Skyrisers. At the 500-foot level of the tower, they created the world’s first rotating glass floor called The Loupe, and they installed a new steel and glass-floored stairway called The Oculus to connect the top three floors. Visitors now enjoy a 360-degree rotating window view of the city, Puget Sound, and Mount Rainier as well as a view of the Needle’s steel superstructure beneath their feet.

Thanks to our long history of collaboration with Olson Kundig, we were asked to fulfill the role of building enclosure consultant throughout this transformative project. During the design phase, our team reviewed the architectural drawings to assess the air, water, thermal, and vapor performance of the new designs. During construction, we conducted field review and assisted with troubleshooting the building performance. As the work was nearing completion, our team conducted a whole-building air leakage test to ensure the renovations would comply with energy code requirements.

Not surprisingly, the high-profile, unique structure presented some challenges for the project team. The building was open to the public and effectively in full operation during the renovations, which required careful space and time management as work proceeded on different parts of the building. The building’s oversized doors and strong external wind pressures at the tower’s tophouse required our air leakage testing team to apply creative problem-solving during a marathon after-hours, night-long testing procedure.

Through our team’s familiar design assist role, we ensured the Space Needle renovations would come as close to complying with current energy code standards as possible for an existing, historic building. The building, which had previously lacked insulation, now has dedicated air and thermal barriers. The historic structure achieved LEED Gold Certification in March 2020. The renovations completed in the summer of 2018 ensured the Space Needle’s 1.3 million annual visitors can experience more spectacular views than the futurists of 1962 could ever have imagined.


March 26, 2020


Olson Kundig

Our Role:

Building Enclosure Consultant

Key Services

Renewal and Rehabilitation
Energy Retrofits

Our diverse team of experienced professionals will collaborate with you and your owner group on your project, whether it involves renewing specific building components or conducting a complete building enclosure rehabilitation. Our knowledgeable staff have the building science and project management expertise to lead you each step of the way, from the initial planning stages through design, budgeting, construction documents, and working with a contractor to implement the work.

Our field review work involves visiting the building during construction to monitor progress, ensure that the contractor has a clear understanding of all requirements, and confirm that the work is being implemented correctly.

In addition to visual field review, we undertake field testing to confirm that the specified materials are being used and the components are correctly installed. We can conduct a range of tests, including water penetration tests, airtightness tests, and membrane and coating adherence tests, to ensure that your project meets the appropriate industry standards.

Michael Kramer | LEED AP

Principal, Senior Building Science Specialist
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David W. Fox | PE

Associate, Senior Project Manager
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