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

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Close-up of "Apartment for rent" sign in red text on black background in front of blurred building

Trump Administration Could Effectively End Housing Voucher Program

Federal officials are eyeing major cuts to the Section 8 program that helps millions of low-income households pay rent.

April 21, 2025 - Housing Wire

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

April 30, 2025 - Diana Ionescu

Ken Jennings stands in front of Snohomish County Community Transit bus.

Ken Jennings Launches Transit Web Series

The Jeopardy champ wants you to ride public transit.

April 20, 2025 - Streetsblog USA

Close-up of white panel at top of school bus with "100% electric" black text.

Driving Equity and Clean Air: California Invests in Greener School Transportation

California has awarded $500 million to fund 1,000 zero-emission school buses and chargers for educational agencies as part of its effort to reduce pollution, improve student health, and accelerate the transition to clean transportation.

April 30 - California Air Resources Board

Aerial view of Freeway Park cap park over I-5 interstate freeway in Seattle, Washington at night.

Congress Moves to End Reconnecting Communities and Related Grants

The House Transportation and Infrastructure Committee moved to rescind funding for the Neighborhood Equity and Access program, which funds highway removals, freeway caps, transit projects, pedestrian infrastructure, and more.

April 30 - Streetsblog USA

"No Thru Traffic - Open Streets Restaurants" sign in New York City during Covid-19 pandemic.

From Throughway to Public Space: Taking Back the American Street

How the Covid-19 pandemic taught us new ways to reclaim city streets from cars.

April 30 - Next City