The Port of Seattle Commission this week approved a final program budget of $399 million for the C Concourse Expansion project at Seattle-Tacoma International Airport (SEA).

The project also released a new fly-through video (see below) with interior and exterior animations of the completed space. Once complete, the project has a goal of LEED v4 Silver certification and will be all electric and fossil-fuel free.

The project will transform the area where C and D Concourses meet by adding four floors to the building’s current three floors. The project will create one floor of office space and three floors of new public space for customer service amenities, adding new dining and retail, premium lounge space, an Interfaith Prayer and Meditation room, nursing room, and outdoor viewing area. The atrium area called the Tree at C will also feature grand seating as well as a performance area for live music.

“This is an exceptional project in terms of elevating the customer experience,” said Port of Seattle Commission President Sam Cho. “However, customer experience is not the only reason why we take on these major projects. The expanded concourse will expand opportunities for local businesses and support the financial stewardship of the airport by increasing revenue opportunities. The whole time we build with intention by focusing on sustainability and ensuring that our construction expands opportunities through the entire community.”

“The C Concourse Expansion project is key to establishing SEA’s future as a five-star airport,” said Lance Lyttle, managing director, SEA Airport. “The C Concourse Expansion will offer more of what guests need by expanding dining and retail options. The project also offers more of what our guests love about SEA, like public art, musical performances, sensory room, mothers nursing room, Interfaith Prayer and Meditation room, and great gathering spaces. This concourse will be a planespotter’s dream, with the Lookout at C providing views of the airfield and the Olympic Mountains beyond.”

The project is also the first at SEA Airport to integrate the Port’s Sustainable Evaluation Framework to ensure that the C Concourse Expansion supports the Port’s goal to be the greenest and most energy-efficient port in North America. The roof will feature a solar photovoltaic array, and the design will leverage materials that have been produced with reduced embodied carbon and healthy materials. Biophilic design elements will also connect guests to nature and the interior will have a high-performance air delivery system to enhance indoor air quality.

Building up to develop amenities and tenant spaces is a key part of the growth strategy of SEA Airport, which is one of the most space-constrained airports in North America. SEA first deployed the “build up” strategy at the new N Concourse, International Arrivals Facility, and modernized Central Terminal. The current SEA Gateway project in the ticketing area also uses a “build up” approach.

Substantial completion of the C Concourse Expansion is estimated in 2026.

Rendering courtesy of The Miller Hull Partnership and Woods Bagot