PDX International Airport’s New Terminal Is a Mass-Timber Marvel

Needing to expand to accommodate 35 million annual passengers by 2045 but constrained by Portland’s urban growth boundary, PDX had to think outside the box when planning its expansion. The result is a case study in sustainability.

2 minute read

September 1, 2024, 5:00 AM PDT

By Mary Hammon @marykhammon


Indoor view of PDX's new massive airport terminal with a wooden beamed roof and skylight.

Ema Peter Photography / ZGF Architects LLP

The first phase of the nearly $2 billion expansion and renovation of Portland International Airport, commonly known as PDX, opened in August. It’s a novel project that has turned PDX into America’s largest mass-timber airport and, according to a recent article from Metropolis, represents a massive milestone for the mass-timber industry. It’s also an example of innovative, creative thinking to address a spate of challenges, including limited space for expansion because of the local urban growth boundary, lack of feasibility around building conjoining existing buildings, the need for seismic resilience against earthquakes, and the fact the existing terminal needed to stay operational during construction, and a desire for sustainability. The solution? Prefabricate a nine-acre wood roof at the edge of PDX’s grounds and slide it into place over top the existing, operational terminal.

“By choosing [a] rebuild over a new airport, the project reduced its carbon footprint by 70 percent, but this required complicated choreography,” Brian Libby, reports for Metropolis. The roof is made with 3.5 million board feet of Douglas Fir sourced from landowners and mills within a 300-mile radius of the airport. According to the article, “The just-completed first phase, built underneath [the timber roof], includes new check-in counters, a Market Hall lined with local businesses, enlarged security checkpoints, and a so-called ‘walk in the forest’: that includes 5,000 plants and 72 mature black walnut, ficus, and olive trees, courtesy of Portland landscape architecture studio PLACE. Phase 2, with passenger exit lanes, additional shopping-dining areas, and north-south views through walls of glass, opens in late 2025.”

Saturday, August 24, 2024 in Metropolis

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