A Policy-Focused Roadmap for Reducing Embodied Carbon
Policy action on embodied carbon is growing quickly. 2021-2023 has seen an unprecedented number of introduced and passed policies targeting embodied carbon reductions in the building and infrastructure sectors in the US, Canada, and internationally. Policies aimed at reducing the embodied carbon of building and infrastructure projects and construction materials typically leverage life cycle assessment (LCA) as a methodology to measure the impacts of a product or project and compare them against a percentage reduction target or embodied carbon performance standard (i.e., global warming potential (GWP) limit).
The effectiveness of policies in reducing embodied carbon relies on the health of the underlying LCA ecosystem – the standards, guidelines, data sources, tools, and actors/organizations that constitute the interdependent building blocks of LCA – to create consistent, reliable estimates of embodied carbon to report and benchmark products and projects.
Existing standards, data, and tools have enabled the growing action and knowledge on embodied carbon we see today, but the shift from voluntary best practice to incentives and regulations has increased the need for access, consistency, and transparency. For effective policy, federal and state government agencies, policymakers, and national/international NGOs need to take on leadership to expand these efforts, create more standardization and coordination across siloed sectors, and ensure equitable representation and participation in standards development and programs.
An “ideal” LCA ecosystem optimized for policy would be:
- Open and transparent through shifting the balance from proprietary data and models to open, high-quality data in public repositories and investing in open data infrastructure.
- Accessible through expanded access to training, streamlined processes and tools for reporting, and financial support for those who really need it.
- More comparable and reliable. Differences in LCA results should reflect differences in the carbon footprints of products or projects, not differences in the data, tools, and methodologies used by practitioners.
- Globally harmonized to streamline the use of LCA data and tools across borders and sectors.
- Keep pace with new materials, technologies, and processes to better track and support decarbonization through filling gaps in standards, data, and tools to explore and measure new and alternative materials and technologies.
This roadmap lays out steps towards achieving this ideal LCA ecosystem across four critical areas:
- Foundational LCA: foundational building blocks related to all scopes and scales of LCA;
- Product LCA: assessments of individual products, product types, and materials;
- Building LCA: assessments of buildings or parts of buildings (e.g. a bay, a wall assembly, the structure), also commonly referred to as whole building LCA;
- Roadway LCA: assessments that include pavements and potentially other additional roadway infrastructure components such as bridges, tunnels, sidewalks, etc. This report considers the more commonly used term “pavement LCA” (FHWA 2016) to be a subset of “roadway LCA.” Roadway LCA is a subset of the larger category of infrastructure.
The findings in this report are based on a review of existing reports and literature, expert interviews held January – April 2023, and virtual workshops held in April 2023 to collect input from 44 different organizations across the US and Canada representing perspectives from architecture, engineering, and construction (AEC) professionals, manufacturing, LCA practitioners, NGOs, and government agencies.
The research team from the Carbon Leadership Forum at the University of Washington College of Built Environments:
- Meghan Lewis, Senior Researcher, Carbon Leadership Forum
- Brook Waldman, Researcher, Carbon Leadership Forum
- Stephanie Carlisle, Senior Researcher, Carbon Leadership Forum
- Brad Benke, Researcher, Carbon Leadership Forum
- Kate Simonen, Executive Director, Carbon Leadership Forum
Author contributions: Writing – original draft: M.L. and B.W.; Writing – review and editing: M.L., B.W., S.C., B.B., K.S.; Conceptualization: M.L., B.W., S.C., K.S.; Visualization: M.L., B.B.
Advancing the LCA Ecosystem: A Policy-Focused Roadmap for Reducing Embodied Carbon is licensed under a Creative Commons Attribution 4.0 International Licence.