Green building programs in North America recognize the value of LCA in sustainable design.
Life cycle assessment (LCA) provisions in LEED®, Green Globes®, the IgCC and CALGreen are easier to achieve than they look. Similarly, the embodied carbon reporting requirements in the Living Building Challenge, the CaGBC Zero Carbon Standard, and the City of Vancouver Green Buildings Policy for Rezonings aren’t difficult. This page briefly explains the LCA incentives in each of the programs and points to the right Athena resources for help.
LCA addresses two big gaps in traditional approaches to sustainable design. First, LCA substitutes meaningful environmental impact metrics for much of the current guesswork. Second, LCA accounts for the embodied environmental burdens of construction. Embodied impacts are typically ignored, even though they constitute the vast majority of environmental burden for the first portion of a building’s life and need to be reduced if we’re serious about climate change mitigation.
Several green building programs in North America have incentives for designers to use LCA to guide measurable environmental improvements in new construction. Many of the programs use a similar “reference building” comparative approach: teams earn compliance by showing that the final building design (core and shell) has lower LCA impacts than a reference building – typically, this would be an earlier design iteration. Conducting LCA during the design process creates an initial performance benchmark to beat, helping inform decisions as they evolve from conceptual design through design development.
North American green building programs with LCA credits:
LEED: The MR credit, “Building Life-Cycle Impact Reduction” (option 4) was new for version 4 and is still evolving. In LEED v4, the base credit is worth three points, an additional point is available for exemplary performance, and in many parts of Canada another point is available for regional priority. Compliance requires showing improvement over a reference building. In LEED v4.1, simply conducting an LCA earns one point. Showing improvement over a reference building earns between two and four points.
Green Globes: See New Construction (March 2018 release) – Materials and Resources Section 188.8.131.52 Path A. This is an LCA performance path option for building core and shell worth 33 points (versus 20 points for the prescriptive path). Compliance requires showing improvement over a reference building.
IgCC: The 2018 International Green Construction Code, Chapter 9, offers an LCA performance path alternative to prescriptive material requirements. Compliance requires showing improvement over a reference building.
CALGreen: The 2016 California Green Building Standards Code, Section A5.409.2, has a performance path alternative to prescriptive material requirements. Compliance requires showing improvement over a reference building.
North American programs with embodied carbon:
Living Building Challenge: Projects must conduct LCA, report total embodied carbon and purchase an offset for embodied carbon.
CaGBC Zero Carbon Building program: Project teams must conduct LCA and report total embodied carbon.
City of Vancouver: Projects applying for rezoning can choose two paths for meeting green building requirements; one path includes LCA and reporting total embodied carbon.
ILFI Zero Carbon program: Project teams must conduct LCA, report total embodied carbon, purchase an offset for embodied carbon, and embodied carbon “must not exceed 500 kg CO2e/m2.”
Need help getting the credits?
The Athena Impact Estimator for Buildings (IE4B) is a free software tool that is key to earning these credits. This software was developed specifically for North American construction-industry professionals and requires no special expertise to use. The IE4B’s inherent LCA methodology, cradle-to-grave system boundary and inventory datasets make compliance with these green program requirements easy. To get started:
- Watch CaGBC on-demand webinar “How to earn the LEED v4 LCA credit”, worth 1.5 GBCI CE hours
- Watch our 1-hour introductory webinar on LCA and the IE4B
- Get the free IE4B software
- Watch tutorial videos to help get you started with the software
- Get the user manual for the IE4B
- Get our guideline to LCA credits in green programs
- Join our mailing list so we can keep you posted on new information and resources
- Read Morrison Hershfield’s paper, ‘LEED V4 LCA Credit and Case Study’
- If you’d like to engage us to do it for you or coach you through it, contact us.