Microsoft is exploring an innovative approach to reduce its carbon footprint by constructing data centers using wood. The company is building two data centers in Virginia made from cross-laminated timber (CLT), a fire-resistant prefabricated wood that Microsoft claims offers a significant reduction in carbon emissions compared to traditional steel and concrete structures.
The concept of a wooden data center may seem unusual, but Microsoft engineers have developed a “hybrid” design that combines wood, steel, and concrete to support the company’s decarbonization goals. CLT is used in parts of the building, including the exterior, to supplement concrete and steel throughout the two-story structure.
According to Microsoft, this hybrid model will reduce the embodied carbon footprint of these facilities by 35% compared to conventional steel construction and by 65% compared to typical precast concrete. “A lot of our suppliers are on the same journey as we are,” said Richard Hage, Microsoft’s Director of Global Data Center Engineering Strategy. He noted that many companies are “implementing key initiatives to lower the embodied carbon of their materials and their products.”
CLT is specifically designed as a low-carbon product, using abundant wood sources and requiring less energy-intensive manufacturing processes. The wood is crafted by gluing together three to nine layers of timber stacked in alternating directions, then pressing them into a solid panel. CLT’s resilience is evident in its high heat tolerance, as it forms a protective char layer that insulates and maintains the structural integrity longer than steel under extreme temperatures.
This isn’t Microsoft’s first venture with CLT; the material was previously used in the construction of the company’s Silicon Valley headquarters in 2021. “We’re constantly trying to validate the suitability of these novel materials for use in a data center environment,” said David Swanson, a principal engineer at Microsoft involved in data center design. “We want to make sure that they’re going to perform, they’re going to be safe, they’re going to be resilient, and provide all the features that we’ve grown accustomed to over these hundreds of years with other materials.”
Microsoft’s wooden data centers are part of its broader sustainability mission to become carbon-negative by 2030 and to remove from the atmosphere all the carbon it has emitted since its founding in 1975 by 2050. In addition to using sustainable building materials, Microsoft is also seeking carbon-neutral energy sources for its growing digital infrastructure. Recently, the company signed a deal with the operator of the Three Mile Island nuclear plant to power its data centers with carbon-free energy. Microsoft previously innovated around water cooling via underwater data centers and continues to set new standards for sustainability in data center construction.
