Due to concern over climate change, there is an increasing desire to limit new carbon dioxide emissions and to reduce atmospheric carbon dioxide levels. Specific efforts include taxing carbon emissions, capping carbon emissions and selling emissions allowances, and rewarding activities that avoid new carbon emissions or that capture and store carbon from the atmosphere.
Cross laminated timber (CLT) is a relatively new product that enables mass timber construction to replace steel and concrete in mid-to-high-rise buildings. Wood materials offer substantial ‘carbon benefits’ by storing carbon in the product, and by avoiding the large amounts of new carbon emissions associated with the use of fossil carbon-based material options (e.g., concrete and steel).
In this analysis, we propose that the carbon benefits of mass timber construction could be valued as a carbon offset, much in the same way that the carbon savings of building a wind farm or solar power plant are currently being marketed for avoiding fossil-fuel electricity generation, or additional forest growth is being sold as carbon storage. Using a range of carbon prices, we calculate the potential carbon offset values of some mass timber construction projects located in the United States. The estimated total carbon benefit, including avoided emissions and carbon storage in wood materials from those mass timber construction projects averaged 0.38 tCO2e /m2 of floor space, representing carbon values for projects ranging into the millions of dollars. Future trends in carbon price will greatly affect the practical implications of any carbon offset program for mass timber construction.