Wood Building Carbon Calculator Updated

The calculator, which measures the carbon benefits of a wood building, now includes new options for mass timber buildings.

A recently updated version of WoodWorks’ free carbon calculator now provides more options for buildings made from cross-laminated timber (CLT) and other mass timber products. Using wood products that store carbon, instead of building materials that require fossil fuel energy to manufacture, can help reduce greenhouse gases.

wood building
According to the updated WoodWorks Carbon Calculator, the new Candlewood Suites hotel at Redstone Arsenal, which is made entirely from cross-laminated timber, stores 1,276 metric tons of CO2 (equivalent) in its wood products. (Photo: Lendlease)

To calculate the carbon benefits of a wood building, users access the carbon calculator and enter nominal wood volume information. The calculator then estimates:

  • How much time it takes U.S. and Canadian forests to grow that volume of wood
  • The amount of carbon sequestered in the wood products, and
  • Greenhouse gas emissions avoided by not using more fossil fuel-intensive materials.

It also uses the U.S. Environmental Protection Agency’s Greenhouse Gas Equivalencies Calculator to equate the total carbon benefit to number of cars off the road and home operational energy.

“The carbon calculator is a useful tool for building owners and designers who’d like to gain insight on the environmental value of alternate designs,” said Bill Parsons, Senior National Director of the Architectural & Engineering Solutions Team at WoodWorks. “It also provides information that allows them to express the carbon benefits of their wood building projects.”

For example, the new four-story Candlewood Suites® hotel at Redstone Arsenal, developed and designed by Lendlease, includes 58,481 cubic feet of CLT. Enter this information in the calculator, and it estimates that:

  • U.S. and Canadian forests grow this much wood in 5 minutes.
  • The CLT in the building stores 1,276 metric tons of carbon dioxide (CO2) equivalent.
  • Using this volume of CLT resulted in avoided emissions of 494 metric tons of CO2.
  • This equates to 374 cars off the road for a year, or the energy to operate 187 homes for a year.

The carbon calculator, which was already robust in terms of lumber, engineered wood products, decking, siding and roofing, was expanded to include new mass timber products available to North American building designers. Mass timber products such as CLT and nail-laminated timber (NLT) may now also be selected for use in a mass timber, light-frame/post and beam, or combination structural system.

Results are based on wood volumes only and are estimated based on research by Sarthre, R. and J. O’Connor, 2010, A Synthesis of Research on Wood Products and Greenhouse Gas Impacts, FPInnovations.

The carbon calculator, as well as a complete list of changes, references and assumptions, can be found here.