There is an old saying that whatever is old is new again, and timber frame suppliers are able to point to a natural material that has existed for millions of years longer than humanity itself as the future of architecture.
Most of the major timber frame projects have either been accommodation or offices, focused on not only the aesthetics and ecological benefits but also the potential health benefits of such a biophilic space.
However, timber framing is extending beyond landmarks, office buildings and “plyscrapers” into major pieces of transport infrastructure, and one of the most unexpected examples of this in action is the emergence of timber-framed airports.
At least two major projects are in progress on airports primarily made from timber local to the area, and the results are both beautiful and rather surprising.
PDX Next
The newest terminal building at Portland International Airport is close to completion and is somehow even more striking today than it was in 2019 when it was initially proposed.
Known as PDX Next, the construction project is made up of 3.3m board-feet of Douglas Fir tree, a local softwood timber indigenous to the region and one that yields more timber than any other tree species in North America.
This consists of a wavy roof that uses over 400 80-foot-long arches made from extremely strong glulam, a panel roof made from Mass Plywood, and a lattice design inspired by local forestry.
Four local tribes (the Yakama Nation, the Cowcreek Band of Umpqua Tribe of Indians, The Skokomish Indian Tribe and the Coquille Indian Tribe) harvested the timber in sustainable ways certified by the Sustainable Forestry Initiative.
Oregon and the Pacific Northwest are particularly well-known for their forestry tradition and the design is keeping in tribute to that, as well as having biophilic and carbon-reducing benefits that are both highly desirable in the stressful environment of an international airport.
One particularly potent benefit of using timber construction is its prefabricated nature. The entire roof was constructed half a mile away before being cut into sections that were 100 feet by 300 feet.
These sections could be fit together over a year, allowing passengers to see the roof being built above them but with no major disruption, something vital for a highly-used international airport.
There is also an offsetting incentive in creating an airport that is low-energy and ideally carbon-negative throughout the whole life cycle of the airport and its materials.
It must be noted that the building is not entirely timber and glass; much of the building is repurposed from the old terminal, and “green” concrete is used, but in a much lower amount than would have been necessary with a more conventional terminal construction.
There are also green spaces inside the complex, facilitated by a much greater focus on natural light, as well as 20 new shops and restaurants.
Given the aerospace industry’s infamous and justified reputation for being a carbon-intense industry, this airport is one of the green shoots of potential change as transportation as a whole gets greener. It is far from the only one.
Raumfachwerk
Known as the space frame project, Zurich Airport’s timber-frame terminal is similarly under construction and is not expected to be completed until 2031.
Whilst Switzerland’s largest city also has a tradition of forestry, timber and ecological harmony, the main driving force for Raumfachwerk is simply to provide the best and simplest passenger experience.
Airports are complex structures to build because vital regulatory changes are so regular and so substantial. This makes them somewhat infamously complicated to navigate and inherently modular in construction.
Getting lost in an airport is a rite of passage for many tourists because of how huge and labyrinthine this is, but the intention of using a timber space frame is to eliminate as much of this complexity as is feasibly possible whilst using locally sourced and sustainable materials.
The renders are utterly striking, showcasing a vivid lattice of timber that holds what was described as “solar shingles”. These panels help to provide power to the airport and help further reduce reliance on carbon-intensive power sources.
However, with this unique design comes added complexity, which is why whilst Portland’s new terminal took five years to construct, Zurich passengers will have to wait another seven years for the space frame project to be completed.
However, the sheer audacious ambition of the project is likely to inspire other timber frame airports in areas with a sustainable forestry tradition, and Portland proves that these ideas can exist as more than mere renders.