Microsoft’s experimental wooden data centres combine traditional materials with billion-dollar investments and supply chain reforms to tackle tech’s growing carbon footprint, offering a blueprint for sustainable digital infrastructure.
In northern Virginia, Microsoft is revolutionising data centre construction with an unexpected material: wood. The company utilises cross-laminated timber (CLT) in a hybrid approach that combines this engineered wood product with steel and concrete. This innovative method promises to reduce the facilities’ carbon footprint by 35% compared to conventional steel construction and an impressive 65% compared to typical precast concrete structures.
The secret lies in CLT’s unique properties. Made from spruce, pine, or Douglas fir, this engineered wood is created by glueing together three to nine layers of timber stacked in alternate directions and pressing them into solid panels. Unlike steel, which can deform under high temperatures, CLT develops a protective char layer that maintains structural integrity longer. The sustainably harvested CLT will replace substantial portions of the thick concrete traditionally used for flooring and ceilings, with only a thin concrete layer applied for waterproofing.
Beyond wood: reimagining the supply chain Microsoft’s wooden data centres represent just one component of a comprehensive sustainability strategy. The company is fundamentally transforming its construction practices through new contract requirements and implementing strict low-carbon specifications for materials and equipment. As part of this transformation, Microsoft will require selected high-volume suppliers to use 100% carbon-free electricity by 2030.
David Swanson, a structural engineer working on Microsoft’s data centre design, notes that while CLT currently commands a 5-10% premium over traditional materials for single-family homes, it can be cost-effective for large projects due to reduced construction time and labour needs. The material is prefabricated offsite and can be installed more quickly and safely than conventional steel structures.
Investing in a low-carbon future Microsoft is backing various sustainable construction technologies through its $1 billion Climate Innovation Fund, which has already committed $761 million. The fund focuses on innovations that can achieve mainstream adoption by 2030, including:
Stegra’s green steel plant in Sweden is designed to cut carbon emissions by up to 95% using hydrogen from renewable energy. Boston Metal’s oxygen-generating steel production process Electric Hydrogen’s renewable electricity-powered hydrogen production CarbonCure’s carbon-capturing concrete Prometheus Materials’ microalgae-based zero-carbon cement The challenge is substantial – according to the World Economic Forum, steel manufacturing and cement production contribute approximately 15% of global carbon emissions. Brandon Middaugh, manager of the Climate Innovation Fund program, emphasises Microsoft’s dual role: “What’s not so common is to see an investor like Microsoft come to the table and say I want to both provide you with capital and also sign a contract to buy the output.”
Scaling sustainable solutions While Microsoft has achieved a 6.3% reduction in direct emissions over three years, the company faces growing challenges with indirect emissions, which have increased by 30.9% due to data centre expansion.
Jim Hanna, who leads sustainability for Microsoft’s data centre engineering team, acknowledges the complexity: “We have to be system thinkers across the entire value chain of these materials that go into our data centres and the equipment that supplies our data centres. That’s what makes it hard but certainly not impossible.”
While innovative, the wooden data centre initiative represents just one step in addressing the broader challenge of sustainable digital infrastructure. The success of these initiatives will ultimately depend not just on the technical viability of new materials but also on Microsoft’s ability to scale these solutions across its rapidly expanding network.
As Thomas Hooker from Thornton Tomasetti notes, “Microsoft is in a unique position just because they’re so large. They can almost be like a market mover and to some extent push some of these technologies to more widespread use.”