Life cycle assessment (LCA) is a performance-based approach to assessing the impacts building material choices have on the environment. When considered over a building’s lifetime – from harvest of raw materials through manufacturing, transportation, installation, use, maintenance and disposal or recycling – wood performs better than concrete and steel in terms of embodied energy, air and water pollution, carbon footprint and global warming potential.
With attention turning away to sustainable design and LCA-based tools that identify the lowest impact alternatives, more designers will become familiar with the environmental advantages of wood and wood products will be a building material of choice for a growing range of applications.
LCA is a powerful tool for illustrating the full life-long environmental impacts of choosing one building material or another and is now incorporated into many green building standards. Worldwide, a number of tools are available for LCA of materials, assemblies and buildings, but in North America there are two, both offered by the Athena Institute:
The chart below showcases the whole building life cycle assessment materials and operational energy use in the Wood Innovation & Design Centre (WIDC). The environmental performance of the WIDC, compared to the baseline building, was reduced by 10% or more in six of the seven reported categories, when both operational energy use and materials were considered. When looking at impact considerations from materials alone, environmental performance improvements for WIDC were 10% or more for all environment indicators compared to the baseline building. Environmental performance differences between the two buildings were largely due to differences in the structural system used.