A 12-story highrise building is set for construction at the corner of Northwest 10th Avenue and Northwest Glisan Street. But this building stands out from the scores of new highrise construction in one significant way: it will be made of wood.
It uses a technology called cross-laminated timber. Giant panels of wood are made out of many layers of timber sheets that are very tightly pressed together. The wood comes from timber in rural Oregon, and the panels themselves will be made long before they arrive at the building site.
Thomas Robinson is the founder of LEVER Architecture, the Portland-based firm that is part of this project. He said that this construction method can be likened to “an incredibly large Ikea cabinet”.
Instead of pouring large amounts of concrete and fashioning the right parts on the building grounds, cross-laminated timber panels can be engineered near the forests from which they came and then shipped straight to the construction site. Robinson told OPB’s Think Out Loud this makes construction much less obtrusive.
“When you think of construction, it’s something you think of as very noisy and a little bit messy. What’s great about this type of technology is that these panels will need to be made very close to where the forests are located and timber is harvested.”
Cross-laminated timber was first pioneered in Austria and Germany in the 1990s, but it is only now reaching American shores. The building that Robinson and his firm are working on will be the first wooden highrise in the United States.
“The idea is there’s a central wood core, and that’s where the stairs and elevators are housed, and that core would be visible all the way up the building,” said Robinson. “We really want people to see the fact that this is not your typical highrise.”
Thomas Maness, dean of Oregon State’s College of Forestry, said the benefits don’t stop there. He argued that wooden highrises could create new jobs in rural parts of the state.
“This is a huge opportunity for rural Oregon,” Maness said. “We’ve seen massive reductions of employment in rural communities and we’re experiencing real poverty in some of these communities.” He cited wooden highrise buildings as “an opportunity to create good manufacturing jobs that can support families, and to do that based on resources that we already have.”
When asked about whether wooden buildings would stand up to fires and earthquakes, Robinson said that his team thought it through by “oversizing” the structure, giving the building more time as a fire burns at a constant rate. He also pointed out that the wood panels comprising the building will be very different from the timber frames most people are used to seeing in their homes.
“Large pieces of wood have an inherent fire resistance,” Robinson said. “When you think about forests, part of a natural cycle is forest fires, and the larger trees survive.”
As for earthquakes, Robinson said that and his team have been “building on global research” done in the wake of other significant earthquakes around the globe. His firm was part of a team that received $1.5 million from the U.S. Department of Agriculture, and “part of the grant is to pay for the testing to confirm that we’re actually meeting those standards.”
Maness added that a potential uptick in CLT would fit within Oregon’s standards of sustainable forest management.
“Only 20 percent of our lands are actually managed for timber,” Maness said. He also pointed out that cross-laminated timber would come from trees that are already being grown instead of from new timber harvests.
“What we’re really interested in is the ability to reduce our CO2 emissions,” he said. “Trees take CO2 out of the atmosphere, and concrete puts CO2 back in. This is a great way for us to reduce our global carbon emissions, and at the same time build healthy, sustainable buildings.”
When asked about the affluent location of the building, Robinson said that he sees the project as “sitting between the intersection of social justice, environmentalism, and economic opportunity.” He said that the mixed-use building will include housing and office space for Beneficial Bank and Albina Bank, while the first floor will include a public space that introduces visitors to how wooden buildings are constructed.
Robinson also said that he hopes this building will show the viability of wooden highrises and serve as a model for the region and the country.
“At the regional scale, it promises to create more demand for these types of wood and be a catalyst for future projects, said Robinson. “And I think that’s something that will extend out from Portland on a national level.”