Is America finally on board with mass timber buildings?

The International Building Code’s approval of mass timber in buildings up to 18 storeys could be the catalyst for its widespread adoption in the US


  • Gregory Scruggs

24 November 2021

Timber apartment building Vienna

HoHo Vienna. Photo by DERFRITZ

In 2014, Seattle architect Susan Jones was having a hard time securing planning permission for her house. She had designed a 139m² house built primarily out of cross-laminated timber (CLT), a building material that was new to the city’s planning officials. Six years later and the architect’s firm, atelierjones LLC, is the design force and Architect of Record behind an eight-storey mass timber building with 126 units of housing.

How did Seattle go, in just six years, from quibbling with an architect over a single-family home’s use of mass timber to rubberstamp a hefty mid-rise that will be home to hundreds of people? Thank the International Building Code (IBC), whose 2021 edition approved the use of mass timber in buildings up to 18 storeys, an increase from the previous five storeys for residential and six for office. Washington State, where Seattle is located, became the first US state to adopt the more wood-friendly code, which Jones helped draft while serving on the International Code Council’s Tall Wood Building Committee.

“As a third-generation Washingtonian, who grew up among its forests, I am deeply optimistic about the impact these code changes will have on our forests' health and long-term sustainability,” she said at the time.

With the IBC’s blessing, local governments across the US are adopting building codes that permit widespread use of mass timber as a building material. And the forest-rich Pacific Northwest region is pioneering domestic design, production, and construction. The US is playing catch up with fellow timber producing countries like Canada and New Zealand, which in turn are still years behind the mass timber vanguard of Northern Europe that adopted building codes ahead of IBC approval. But as mass timber moves more into the global mainstream, the potential benefits are tantalising.

“Mass timber is not just another wood product,” says University of Washington economist Indroneil Ganguly, who studies mass timber. “It is a wood product that displaces one of the world’s most polluting products: concrete.”

Jumpstarting a mass timber movement is not as simple as market supply and demand, or a case of permit it and they will build. There are constraints all along the supply chain from tree to townhouse. Cost is a major factor in New Zealand, where Linda Lodetti MRICS, a South African quantity surveyor for Prendos, is based. Lodetti estimates that mass timber imported from Europe was up to 50% cheaper than domestic supply when began working on projects in Christchurch in 2012. In turn, mass timber routinely costs 30% more than steel. To help builders understand the best cases for mass timber, she wrote Costing Timber Buildings, a costing guide published by NZ Wood in March 2020.

“The timber industry was criticising quantity surveyors,” she says. “In turn, quantity surveyors were complaining there is no data and mass timber is always expensive, so we were trying to get to a positive scenario of when it is best to use timber.”

In the less mature North American context, cost is less of an immediate factor. Instead, it’s public sector support that’s lacking. Canada’s backing of the Structurlam and Nordic Structures mass timber plants, and not-for-profit sector proof of concept in the US are the key ingredients before the risk-averse construction industry gets fully on board.

“The building industry in North America is extremely conservative,” says Ganguly. “We don’t use innovative materials easily, especially when they are structural.” He points to the slow adoption of oriented strand board over plywood as one example of this phenomenon.

“Construction is the last major industry not to be disrupted by technology,” argues Tobey Levey, vice-president of Real Estate Transactions for Forterra, a Washington State-based land conservancy investing in a regional mass timber pipeline. “We are literally in the late 19th century. That antiquation is multifactorial: The risk of innovating when a contractor could go out of business any minute from a single project is absurd.”

Levey has plenty of experience securing mass timber components and qualified labour for Forterra’s under-construction mass timber production facility. It has been an exercise in the convoluted nature of the US building trades, with middlemen marking up by double the cost of materials sourced from far and wide. Forterra is betting that its facility will be a proof of concept that only a not-for-profit backed by public sector financial support can pursue in this risk-averse environment. If successful, the outcome will do more than just revitalise a rural economy in a sawmill town 55 miles north-east of Seattle.

“When you go directly from a forest to a mass timber plant to a home, you cut out the corruption inherent in our building procurement system,” Levey says. “The danger is that you are disrupting a 150-year-old gravy train that does not want to change and is perfectly comfortable taking in fees and paying off middlemen to implement and reinforce a monopoly and constantly claiming a constraint on supply.”

Forterra is hardly the first to take a crack at disrupting the construction industry. In 2015, Silicon Valley entrepreneur Michael Marks founded Katerra with the goal of vertically integrated construction through heavy reliance on, among other materials, mass timber. In 2019, the company built a mass timber production facility in Washington State that purported to be the highest volume factory in North America. The company gobbled up architecture and design talent working with mass timber.

But in June 2021, Katerra went bankrupt and the plant closed, throwing promised rural industrial jobs into limbo. (Vancouver-based wood products company Mercer International bought the plant in August; they declined to comment for this story.) The construction tech start-up had burned through a spectacular $2bn in six years with only a handful of completed mass timber buildings to show for its immense investment.

"Katerra failed in a big Silicon Valley way, but they were a contributor to innovation,” says Levey.

Many former Katerra employees went on to keep evangelising for mass timber. Among them is Craig Curtis, the former chief architect for Katerra and now director of emerging building technologies at the Seattle office of West Coast architecture firm Mithun. His firm is currently engaged in design for eight mass timber projects.

“Most of our clients at least ask about it and are interested even if not everyone is ready to commit,” he says.

As mass timber gears up for widespread adoption in the US, Levey is optimistic about this better late than never outcome. “It’s the American way,” he says. “We’re always a little late, but then we do it to scale and often better than the rest of the world.”

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“The building industry in North America is extremely conservative. We don’t use innovative materials easily, especially when they are structural” Indroneil Ganguly, University of Washington

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