Century Project, The Space Needle Renovation

Structural Designer


Client Name

The Space Needle Corporation


Seattle, USA

Hoffman Construction

Olson Kundig

Seneca Group - Development manager
Front - Glazing consultant Images: © Nic Lehoux


A globally recognised symbol of Seattle, standing at 184m and attracting more than 1.3 million visitors per year. Cutting-edge techniques preserved the building’s historic exterior while improving the guest experience and clarifying the original conceptual design vision. 


Judge's comment:

Over 160 tonnes of glass was incorporated into the retrofitted structure to create a new rotating glass floor and increasing the glazed area by more than 200%, giving visitors an unobstructed 360-degree view of Seattle’s skyline.

The degree of structural retrofitting was significant, with Arup remaining on call 24 hours a day to assist the contractor throughout the 11-month contact period.

The judges were particularly impressed with the introduction of the two curved feature stairs that connect the two public levels that are over 150m above ground. In view of their high level of use, Arup had to pay close attention to their dynamic response over a range of loading conditions, detailing them so that they performed under both normal and seismic loads.

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