In the lighting world, we usually think of reducing carbon by increasing efficiency of energy use. However, there is a new push to reduce the carbon used to create construction materials, known as embodied carbon. This matters in the fight against climate change. Building materials and construction comprise about 11% of global energy carbon emissions.
The US Green Building Council (USGBC) and RMI (formerly Rocky Mountain Institute) release a new report titled, Driving Action on Embodied Carbon in Buildings. The report covers:
- The state of the data on embodied carbon
- The opportunity to reduce embodied carbon from standard building practices
- Current and emerging benchmarking standards
- The carbon intensity of specific materials
- Embodied carbon savings potential from reuse, recycling and circularity
- Assessments of emerging and future low-embodied-carbon technologies
Another recent report, The Embodied Carbon Reduction Roadmap, was authored by Arup for the Natural Resources Defense Council (NRDC). It explores policy options to support a wide range of strategies that can be deployed to address embodied carbon across the construction industry. The report focuses on California as a case study due to its track record for setting ambitious climate targets and for starting to adopt progressive embodied carbon policies.
California is now the first state in the country to require embodied carbon reductions in its state energy and sustainability code, CALGreen. The new code changes become effective July 1, 2024, and apply to commercial buildings over 100,000 square feet and school buildings over 50,000 square feet. This California code creates three pathways to compliance:
- Building reuse – reuse at least 45% of an existing structure and exterior.
- Performance – complete a life cycle assessment demonstrate 10 percent lower embodied carbon than a calculated baseline.
- Prescriptive – provide environmental product declarations (EPDs) for steel, glass, mineral wool, and concrete that are on average lower than the standard global warming potential for those materials.
Expect to see more activity around the country on reducing embodied carbon in construction materials. More information the new CALGreen code can be found here.