The Seattle Gateway Project will reconfigure and modernize the 40-year-old north terminal of the Seattle-Tacoma International Airport. By enlarging the terminal and expanding the security checkpoint, the project aims to improve the flow of passengers and ease the bottlenecks that travelers currently experience.

RDH was retained by HOK as part of the design-build team with the General Contractor, Hensel Phelps, to provide a range of services throughout the project’s design phase. Our early design concept sketches supported the development of a custom metal roofing system hung from the underside of the existing elevated roadway between the terminal’s main ticketing and baggage levels. This novel solution allowed for the existing roadway, which was not originally designed as a roof, to remain in service to airport traffic, while construction activities occur below. We also provided design review services to ensure this roof concept was properly implemented and to provide support for the new façade and entry doors.

During early site visits, our team evaluated the existing structure and aligned the design to as-built conditions. Our team met regularly with HOK, Hensel Phelps, and the Port of Seattle to iterate the design concept. These efforts were intended to confirm the constructability and sequencing of the work, account for ongoing vehicular and passenger traffic throughout the airport, and meet the Port of Seattle’s design standards and maintenance program.

Our Seattle field team, in consultation with our Denver-based design team, is performing construction phase services for this project. These services include field review, performance testing, and construction administration. We remain nimble in our work with the design-build team to support design changes during construction to address as-built conditions, project sequencing, and budget needs.


February 28, 2024



General Contractor:

Hensel Phelps

Our Role:

Building Enclosure Consultant

Renderings By:


Key Services

Early Stage Design Assistance
Field Review

Often the best value that our Façade Structures team can contribute to a project is during the early stage of design. We help our clients explore conceptual design opportunities and support the design team by answering questions such as “Can we actually do this?” “What will this cost?” and “How can we optimize our systems?” Our team is able to assess the interaction between the building enclosure design, energy performance, and ventilation strategies to support the development of advanced and unique building façades. Once we have defined these elements of the project, we are able to better focus our services during the subsequent stages of work.

Andrew Dillenbeck | M.S., PE

Principal, Senior Project Manager
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Kyle Silliker | PE

Principal, Senior Building Science Specialist
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