Published 7:00 am Thursday, March 9, 2023
PORTLAND — From its conception, the new mass timber roof at Portland International Airport was meant to evoke a walk through a Pacific Northwest forest.
Wood for the impressive nine-acre, 9,000-ton roof came largely from sustainably managed forests in Oregon and Washington. A curved lattice structure, interspersed with large oval skylights, gives the impression of being outdoors beneath a thick canopy of trees.
“We wanted it to be not only functional, but to make a statement with our design,” said Vince Granato, chief projects officer for the Port of Portland, which operates the airport. “We wanted to take advantage of what the Pacific Northwest is known for.”
The roof is part of a $2 billion series of capital improvement projects at the airport, called PDX Next, which includes an expansion of the main terminal.
Construction of the roof is now completed, and installation is underway. Sixteen sections were lifted into place between September and December last year for Phase I, which is scheduled to open to the public in 2024.
The final four sections will be installed for Phase II by the end of 2025, Granato said.
Not only will the expanded terminal be able to accommodate 35 million passengers annually, but advocates say the roof will serve as a showpiece for mass timber — specially engineered wooden beams and panels that can be used in buildings instead of steel and concrete.
As the use of mass timber gains momentum, it is sparking conversations about how demand for products could shape forest management practices to supply wood while preserving healthy watersheds and wildlife habitat.
Development of PDX Next started shortly after the airport released its master plan update in 2011, Granato said.
PDX has already finished several projects identified in the master plan. The airport built a consolidated car rental center; added six new gates to Concourse E for Southwest Airlines; demolished the old Concourse A; and opened an entirely new Concourse B in 2021, devoted to Alaska Airlines and Horizon Air.
But the largest piece of PDX Next, Granato said, is the main terminal expansion that began in 2018.
“At some point, we were going to run out of space in the terminal,” Granato said. “We knew we needed to upgrade our building.”
The crown jewel is the eye-catching roof, designed by ZGF Architects in Portland.
Christian Schoewe, a principal at the firm, said the project team initially laid out four guiding ethics for the roof, including customer experience, a visionary design, operational efficiencies and environmental sustainability.
While steel would typically be considered for such an expansive structure, Schoewe said mass timber satisfied the team’s criteria and was more reflective of the region.
“Using wood became kind of an obvious choice,” he said. “When people arrive here, we’re pretty sure they’ll know they’re in the Pacific Northwest.”
Schoewe called the roof “a celebration of craft.” Using wood also helped to offset 41% of carbon dioxide emissions versus building with steel and concrete, he added.
Wood for the roof was sourced from 13 forests in Oregon and Washington, including small family woodlands and tribal nations.
The logs were processed by six sawmills, and manufactured into mass timber beams, panels and latticework at six fabricators.
Traceability was another important consideration, Schowe said. Once it is opened, airport managers and travelers will be able to point at any given section of the terminal roof and know exactly where the wood came from and how it was harvested.
“The goal there was to track as much of the fiber back to the forest of origin as possible,” Schoewe said.
Similar to the farm-to-fork movement for food, mass timber embraces an ethos of “forest-to-frame,” changing the way people think about and relate to buildings.
“I’m grateful that the port (prioritized) that,” Schoewe said. “Now that we’ve shown it’s possible and we know how to do it, we can apply that to other projects.”
In total, the $150 million roof is made from 3.3 million board-feet of wood, all of it Douglas fir. Crews built each section at a construction site about a quarter-mile from the terminal, allowing them to work just 13 feet off the ground and avoid causing disruptions for travelers.
With the first 16 sections now in place, Granato said the airport is excited to show off the roof beginning next year.
“People are going to be blown away when they see this,” he said. “It’s going to be spectacular.
One of the project’s Oregon-based partners, Freres Engineered Wood, provided 73,527 cubic feet of mass plywood panels for Phase I of the roof’s construction.
Mass plywood was patented by the company in response to competition from imports of structural plywood from overseas. Brazilian plywood, in particular, had increased to about 15% of overall U.S. consumption, said Tyler Freres, vice president of sales.
Freres and his brother, Kyle, vice president of operations, first learned about cross-laminated timber during a trip to Europe with professors from Oregon State University.
They returned home eager to create their own version of mass timber, allowing the 100-year-old family operation to maintain a competitive edge in the market.
“We were trying to figure out what type of value-added products we could make out of our own veneers,” Freres said.
The result was mass plywood panels, or MPPs, made by gluing and pressing veneers together to create structural components for wooden buildings. Each panel is made at Freres’ $45 million MPP mill in Lyons, Ore., that was built in December 2017.
Panels are made to specification depending on the project, up to 12 feet wide, 48 feet long and 24 inches thick.
Freres said he is “extremely optimistic” about the future of mass timber. Recently, he said the MPP mill has been setting monthly production records of 35,000 to 40,000 cubic feet, and hopes to add a second shift that would roughly double production.
Making roof panels for PDX was a major opportunity, Freres said.
“Obviously, it’s going to be the type of project that we all as Oregonians are going to be walking through for the next 50 to 100 years,” he said.
Freres said he also hopes the growing success of mass timber will encourage more restoration and thinning of public forests to supply wood and simultaneously reduce wildfire risk.
Nearly all the wood used in mass plywood panels for the airport roof came from salvage logging trees on about 5,300 acres of company forestland that burned in the massive 2020 Beachie Creek fire along the North Fork of the Santiam River, Freres said.
“I really hope that people start to realize that this is the most responsible material that we have to build with into the future,” he said. “If the state and if the federal government would really like to see more buildings built sustainably out of wood, then they need to make the trees available. We can’t just make this out of air.”
Environmental advocates argue that mass timber must be sourced from sustainably managed forests that emphasize biodiversity and healthy watersheds.
Steve Pedery, conservation director for Oregon Wild, said there is nothing inherently good or bad about mass timber as a product.
“The trick is, if it’s derived from sustainably sourced wood, it can be a very good thing, supporting better environmental outcomes,” Pedery said. “If it’s taken from an industrial clear-cut, it’s no better than any other piece of wood coming off of an industrial clear-cut.”
According to PDX, more than 95% of the wood for the terminal roof came from sustainably managed Oregon and Washington forests.
Hyla Woods, a family-run forest in the Oregon Coast Range west of Portland, provided about eight truckloads of logs for the roof. The wood was sent to Kaster’s Kustom Cutting, a small sawmill in Clackamas County, which made much of the lattice for the ceiling.
Peter Hayes, president of Hyla Woods, said they purchased the forest — three properties adding up to about 1,000 acres — in 1986. It began as an experiment, he said, examining ways they could maximize ecological and economic benefits.
“Forests provide a wide range of things, including wood, but not solely wood,” Hayes said. “We feel it’s important to help the forests reach their full ecological potential.”
The forests used to be aggressively logged from the 1920s to the 1950s, Hayes said. Now the landscape is in recovery, he said.
Though trees are logged regularly on the forests, Hayes said they avoid clear-cuts. “Most all of our logging is done through careful thinning,” he said, while preserving larger old-growth trees that store more carbon.
Hayes praised the PDX roof project for embracing frame-to-forest, and for partnering with land managers focused on creating regenerative communities.
“The message from the market has been, ‘We don’t know where the wood comes from, just keep it coming and keep it cheap,’” Hayes said. “In this case, the port and our customers said the opposite — ‘We care where the wood comes from, and we want to have fair trade relationships that leave those places better off.’”
Hayes said he hopes more mass timber projects prioritize sourcing of wood in a way that makes forests and communities healthier and safer.
“We see our partnership with the Port of Portland to be so energizing because we share a commitment to treating local forests and the communities linked to them with respect,” he said. “Our region’s forests are a wonderful gift and the project creatively honors those gifts by making something beautiful, inspiring and useful from the wood that the forests provide.”
Meanwhile, the region is primed for more development of mass timber products.
At Freres, the company’s MPP mill continues to manufacture panels for 20 upcoming projects, including an 18-story residential building in Oakland, Calif. Tyler Freres said it is enough work to keep the mill busy for the next 7-8 months.
Availability of wood, however, is a looming existential problem, Freres said.
The federal government owns 60% of Oregon’s forests, yet those lands account for just 14% of the state’s timber harvest.
On the other hand, 34% of Oregon forests are privately owned but account for 76% of the timber harvest.
Freres said he hopes mass timber will encourage policymakers to accelerate thinning of overstocked public forestland.
“I think people are recognizing that we need to figure out the best way to build our buildings of the future,” Freres said. “I think wood is it, hands down.”
Last year, the Oregon Mass Timber Coalition received a $41.4 million grant from the Biden administration’s “Build Back Better Regional Challenge.” A portion of the grant will go toward construction of a factory at the Port of Portland dedicated to building modular homes using mass timber to address the city’s affordable housing shortage.
Another $24 million in grants will go to further research into the structural, seismic, durability and energy performance of mass timber buildings, led by the TallWood Design Institute, a collaboration between the University of Oregon and Oregon State University.
”I do think people are going to start looking at it more,” said Granato, with the Port of Portland.
