Global demand for wood as a building material is expected to quadruple by 2050. Demand is being driven in part by the rising popularity of mass timber for its aesthetics and eco friendliness. One of the perceived advantages of choosing mass timber panels and components for construction and renovation is their lower production-related greenhouse gas emissions vis-a-vis conventional wood products and other building materials like steel or concrete. But the notion that producing mass timber is carbon neutral—one of its key selling points for developers and AEC firms looking to reduce a project’s carbon footprint—has come under greater scrutiny, and has led one firm, Corgan, to develop a tool that calculates CO2 from mass timber, including the harvesting and transporting processes that, according to a recent paper published by Nature, could add between 3.5 billion and 4.2 billion metric tons of GHG emissions annually to the atmosphere by 2050, the equivalent of roughly 10% of recent CO2 emissions.