International Arrivals Facility at Seattle-Tacoma International Airport

2024 Design Awards Merit Recipient

International Arrivals Facility at Seattle-Tacoma International Airport

A welcoming, light-filled gateway to the United States – the new International Arrivals Facility (IAF) at Seattle Tacoma International Airport (SEA) is a 600,000 square foot addition to the existing airport campus. The most complex endeavor in the airport’s history, the IAF integrates disparate terminal concourses that double international flight capacity. The IAF includes three primary additions: the arrivals hall, arrivals corridor and an 85-foot-high aerial walkway. These additions strategically connect to existing buildings and were designed to facilitate construction to maintain operations throughout. The previous international arrivals sequence directed passengers to a subterranean level and connected via underground transport to baggage claim. The new sequence takes passengers across the active taxiway below with panoramic mountain range views. Descending from the aerial walkway, travelers enter the International Arrivals Hall atrium for baggage claim and Customs and Border Patrol (CBP) processing. The IAF’s sweeping roof arcs reflect the motion of a landing airplane, creating large windows and clerestories. Passengers are greeted with locally-sourced materials, such as the douglas fir thresholds, and river stone terrazzo floors. Exiting, passengers descend a sloped walkway alongside an evergreen forest courtyard, and exit over a creek landscaped with granite slabs and native plants. The building superstructure is exposed eliminating interior cladding and finishes, thereby reducing the carbon intensity footprint. In addition to material reductions, many materials used in the project were sourced within 100 miles of SEA. The high-performance exterior closure in the arrivals hall benefits from abundant natural eastern and northern light throughout.

//comments

This is a really interesting addition to an already incredibly dense infrastructure. The form of the building in the roof is very appropriate for an airport and was a great fit into the existing context. The bridge—to have a structure that airplanes can scoot around and under—was a very a bold move. The jury appreciates how the section responds in scale to the programmatic pieces underneath as opposed to being a continuous unaltered sort of sectional building which would be the expectation here.

//framework for design excellence measures

Measure 1: Design for Integration

The architecture reflects deep consideration of international passengers’ journey. After long, sedentary flights from different time zones, travelers arrive in a place that guides their acclimation. The elevated, aerial walkway and windowed expanses of the arrivals hall maximize daylight, and begin resetting circadian rhythms. The walkway also provides a clear directional pathway from the S Concourse to baggage claim. Rather than building an entirely new international terminal, the project makes use of the existing gates and airport infrastructure. The long-span walkway, hall roof, and gate pods were carefully designed to minimize structural materials and foundations. The building superstructure is exposed eliminating interior cladding and finishes, thereby reducing the carbon intensity footprint. In addition to material reductions, many materials used in the project were sourced within 100 miles of SEA. All occupants benefit from abundant natural eastern and northern light through the high-performance exterior enclosure in the arrivals hall. This is accomplished with 39% window-to-wall and full exterior commissioning, demonstrating performance at six times better than the allowable standard – exceeding the stringent State of Washington Energy Code. Displacement cooling is utilized in high volume spaces providing conditioned air at the occupant level.

Measure 2: Design for Equitable Communities

SEA has multiple stakeholders including the Port of Seattle, airlines, federal agencies, and the local community. Community engagement was conducted at regular Port Commission hearings where the community (public) could offer input and questions for the Port and the project team to address and respond. This regular and continual involvement kept the community informed of ongoing developments with the opportunity to provide community input and advice. Multiple work sessions with Port of Seattle staff on operations and maintenance further defined the criteria set in the program and Project Development Document (PDD) provided by the Port.

Measure 3: Design for Ecosystems

The previous site use was a brownfield site utilized for a bus drop off zone. Environmentally conscientious construction practices included removing 7,163 tons of contaminated soil and 62,405 gallons of impacted stormwater, and diverting a staggering 92% of construction waste away from landfills. Exterior courtyards and public frontage were replanted with all native trees and flora to punctuate the client goal for a Pacific Northwest experience. The IAF is not in a migratory path for birds and therefore no specific bird mitigation is necessary.

Measure 4: Design for Water

Water strategies were determined to aid in the sequencing of construction to maintain the 24/7 airport operation. A purple pipe flush system will connect to a future campus-wide rainwater collection system. Once ready, a tie in location will allow an easy switch from standard water to reclaimed water. In a high-use 24/7 facility, reliable yet water efficient fixtures were selected. The project utilizes the existing cooling tower on the SEA campus.

Measure 5: Design for Economy

The IAF was built to meet the increase in demand and to compete with other West Coast hubs. At the time of design and procurement, Seattle was in the midst of a building boom, making competitive bidding difficult. Outreach to local businesses and trades was key to address affordability. Major trades were procured early and invited to offer input on methods to achieve performance with cost effective measures. By reconfiguring the existing Concourse A to create a dual-purpose secure corridor, the design nearly doubled the number of gates capable of receiving international wide-body aircraft. These “swing-gates” add for future flexibility.

Measure 6: Design for Energy

As an airport without equivalent CBECS benchmarks, code equivalency tables do not apply appropriately. In fact, the Terminal Site EUI Benchmark is 113 kbtu/sf/yr. Simulation results forecast that heating energy will be 34% better than a proposed building and fan energy will achieve 10%. High-efficiency LED lighting is designed to save 8% of energy consumption. The process loads associated with airport operations, specifically baggage handling, will be 17% more efficient than a typical airport due to the deployment of variable frequency drives. In summary, the LEED energy model demonstrated an energy cost savings of 14.4%.

Measure 7: Design for Well-Being

Maximizing daylight was a key design goal. In addition to reducing energy needs during the day, plentiful access to natural light reinforces post-flight circadian rhythms for travelers arriving from distant time zones. The incorporation of landscape and surrounding views as a visual amenity was also central to this approach in connecting passengers with their new environment. Exterior metal surfaces are protected from the elements with non-zinc protective coatings to eliminate water contamination on the local and regional ecosystem.

Measure 8: Design for Resources

As an addition to the existing buildings, the IAF shares vertical enclosures for approximately 30% of the new building footprint. The design approach utilized an economy of materials expressing the superstructure and eliminating superfluous interior finishes. Materials were selected for abuse resistance and a multi-year lifespan. Flooring at primary wayfinding locations is recycled wood blocks further reinforcing the Pacific Northwest feel. While a whole lifecycle analysis was not conducted, many of the materials were sourced within 100 miles of SEA.

Measure 9: Design for Change

Flexibility was a core design principle. By reconfiguring the existing Concourse A to create a dual-purpose secure corridor, the gate pods are able to serve both international and domestic flights. The aerial walkway is designed so it can be converted to departures and the current arrivals configuration as the airport operations evolved to meet passenger demand. The column-free arrivals hall is equipped for changing CBP technology and emergency generators are equipped to connect to the emergency power generators for the SEA campus.

Measure 10: Design for Discovery

Arriving at the IAF provides a welcoming experience for international passengers as it matches efficiency with regional character. Local artists are represented throughout and the connection to nature and natural light is something that all occupants can enjoy. The soaring aerial walkway is 780 feet wide, making it the longest structure spanning an active taxilane in the world. The Port of Seattle staff provided positive responses in support of the design team and topics were collectively addressed and refined with a focus on functionality, durability and a welcoming environment.