US data centre builders are paying more for structural steel and facing longer lead times, with the race to build for artificial intelligence running America’s mills and fabricators at full capacity. That is according to Skanska, the global construction and project development firm, whose director of mass timber and prefabrication, Dean Lewis, told a public webinar earlier this month that data centre customers had shown “a lot of interest” in timber.
“Clients are interested in alternative materials given the supply chain strain in general across all materials,” Lewis said, adding that the timber frame itself generally costs more than steel. Even so, a three-storey office Skanska studied came out close to cost-neutral, he said, once a smaller foundation and lateral system were factored in alongside savings on finishes, facade, and schedule.
The real lead time on a timber job sits in design and coordination rather than at the factory, Lewis said, because that is where teams decide how quickly panels reach the site. Builders’ risk insurance still costs more for mass timber than steel, he added, and Skanska is studying ways to cut those premiums with the US Department of Agriculture.
“Very strong demand for steel and other metals because of the AI rollout,” Tom Park, Skanska’s vice president of strategic supply chain, said of the squeeze. Skanska had flagged waits of 40 to 50 weeks in a summer market trends report released on 1 September, noting particularly strong demand for structural steel from data centres and large-scale manufacturing.
Steel prices were already climbing before the webinar, with cold-rolled coil up 25.3 per cent over 12 months, according to Skanska’s spring report. Aluminium rose 45.3 per cent and copper 29.5 per cent over the same period, which the builder put down to electrification, AI-related demand, and the closure of the Strait of Hormuz.
Unlike steel, mass timber “has proven to be much more stable as of late,” said François Robichaud, partner for market intelligence on wood products and construction at Forest Economic Advisors. He told the webinar that North American plants are still making less cross-laminated timber and glulam than they could, so producers should be able to meet future demand. Skanska said, however, in its summer update that the cross-border tariff fight with Canada would likely also shape lumber costs, even with trade flows steady for now.
In Sweden, EcoDataCenter opened its first cross-laminated timber data centre in Falun in 2019, and timber supplier Stora Enso called the campus the world’s first mass-timber data centre in November last year. Nearly 95 per cent of the structural frame is now cross-laminated timber, said John Wernvik, EcoDataCenter’s chief external relations and sustainability officer. Customers were the hardest to win over, he said, though “acceptance has shifted dramatically” since Microsoft and Meta began announcing timber data centres of their own.
Back in the United States, Skanska found that data centres were the fastest-growing segment of commercial construction, accounting for 5.4 per cent of private non-residential building spending in 2025, up from 1.7 per cent in 2019. The firm is building them itself, booking a US$94 million contract in the second quarter for a single-storey, 38.4-megawatt data centre in Virginia, with work due to start in October.
It comes after Weyerhaeuser president and chief executive Devin Stockfish told analysts in July that speed, rather than cost or carbon, was the objection developers raised to building data centres in wood. He named their own greenhouse gas commitments as the opening, with Weyerhaeuser pressing the case alongside the US Lumber Coalition, while WoodWorks was briefing designers on mass timber for data centre design as recently as June.
In August, Vittorio Salvadori, director of design at TimberBLDR, revealed a hybrid concept that slides cross-laminated timber decks into light-gauge steel-framed data centres to speed construction. Structural steel typically took 18 weeks to fabricate and deliver, Salvadori said, though he heard some sections quoted at up to 48 weeks at the DICE South conference in Arlington, Texas. Big tech now buys up to 10 per cent of all mass timber sold in the United States, he told April’s International Mass Timber Conference.
“Evaluating structural options earlier in the design process can help project teams navigate supply constraints,” Skanska’s summer update advises, especially where data centre and advanced manufacturing work is concentrated. Skanska expects annual US spending on data centre construction to pass $100 billion by 2030, more than twice today’s level.
