Centre for Interactive Research on Sustainability, University of British Columbia, Vancouver, B.C.. Image © Don Erhardt, courtesy naturallywood.com
To initiate change of any kind, one must first be aware of the problem at hand. In the construction industry –which is responsible for 39% of global greenhouse gas emissions and countless other environmental impacts– mastering and understanding the numbers related to its processes is extremely important. But assessing the impact of a product or a material is much more complex than one might think. It includes the exhaustive collection of data about its inputs (for example, the raw materials, energy, and water used) and outputs (such as emissions and waste) associated with each stage of the life cycle. This allows for the quantification of the embodied carbon and other environmental impacts, the identification of where performance can be improved, and provides real numbers for a comprehensive and unified comparison between materials and products.
The Whole Building Life Cycle Assessment (wbLCA) method studies the totality of products present in a building, providing valuable information for decision-making related to the design, construction, operation, maintenance, and eventual demolition or reuse of a building. In other words, it refers to the totality of the LCA (Life Cycle Assessment) for all of the building’s components. Recently, the National Research Council of Canada, in collaboration with the Athena Sustainable Materials Institute, released the national guidelines for wbLCA, which reflect what is practiced in North America. The aim is to harmonize the practice and to aid interpretation and compliance with relevant standards, with the guidelines being updated periodically as it evolves, enabling the calculation of reliable baselines or benchmarks, supporting LCA-based compliance schemes and assisting in the development and use of wbLCA software.