Information from Port of Seattle

Seattle-Tacoma International Airport (SEA) revealed today 30 percent design renderings of its next marquee capital improvement project. The C Concourse Expansion will elevate SEA, literally, by adding four additional floors above the existing building and raising the bar on the airport experience and sustainability. 

The project spans the C and D Concourses with 145,530 more square feet of dining and retail, sought-after amenities such as an Interfaith Prayer and Meditation Room and Nursing Suite, and an all-new, more than 20,000-square-foot Alaska Airlines Lounge. The heart of the space – The Grand Stairs at C – will be an iconic destination that invites travelers to linger with seating, airfield views, music and art, or head upstairs for more elbowroom and dining and retail options. The expansion also encompasses office space for airport businesses, airlines, and the TSA. 

“We have a clear vision for how the airport will look and feel in the coming years,” said SEA Managing Director Lance Lyttle. “Making your experience less stressful and more predictable is at the center of our vision. You can feel the difference now at the newly modernized N Concourse and soon to open International Arrivals Facility. The C Concourse Expansion is what’s next in how SEA serves travelers, and we can’t wait.”  

Bringing In, Seeing Out  

The C Concourse Expansion rethinks the airport experience where design creates an intuitive journey, a sense of calm, and climate consciousness. Miller Hull and Woods Bagot are leading the project’s design concept of bringing in andseeing out to create an interplay of environments between the natural landscapes of the Pacific Northwest and the energy and vibrancy of Seattle.  

The forests of this region inspire the building's design. From the light solariums and the canopy feeling of the Grand Stairs, created by undulating Douglas fir coffers in the ceiling transition down to a singular colossal pillar, travelers will sense the scale and grace of a Pacific Northwest forest. The Grand Stairs create a central gathering space designed to reflect regional public and farmers markets. Dining and retail will frame this tiered, open amphitheater with a stage for live music.  

Next, travelers are drawn to the upper level with restaurants above as well as views and the ability to look out over the entire facade. One of the most unique aspects of the C Concourse Expansion is its height and unobstructed views of the airfield and Olympic Mountains via a lookout deck encased in glass that will be available to all passengers.  

Sustainable Design Strategy  

The Port of Seattle, which owns and operates SEA, is working to be the greenest and most energy efficient port in North America where the health of the environment and the well-being of travelers is paramount. C Concourse Expansion is the first project of its kind to follow the Port’s Sustainable Project Framework, a process to transparently evaluate alternative, sustainable approaches to build capital projects where environmental and societal impacts inform project design, alongside cost and schedule.  

The sustainable features of this project will set the precedent for future capital projects at the Port, including:  

• Rooftop photovoltaics and a solar panel array is projected to provide 15 percent of the C Concourse Expansion energy demand. 
• Creating fossil fuel free systems for heating and tenant hot water and equipment with electricity that will save Scope 3 greenhouse gas emissions.  
• Electrochromic glazing for windows will reduce peak cooling loads and annual cooling energy consumption. 
• Installing dishwashing capability will reduce solid waste from disposal dishware and space for donated food storage will support the airport’s existing partnership with the Des Moines Area Food Bank.  
• Embodied carbon reduction strategies such as lessened steel tonnage and associated manufacturing impacts and decreased cement quantity.   
• Low-flow water fixtures that conserve potable water and a purple system to connect to future reclaimed water supplies.  
• Biophilic design principles will create a connection to the outdoors with natural lighting, landscape features and other elements for a sense of well-being for travelers.