September 30, 2023
What is Embodied Carbon and Why is it Important to Sustainability?
The building and construction sectors are responsible for nearly 39% of global carbon emissions, a significant portion of which comes from “embodied carbon.” As operational efficiencies in buildings improve, embodied carbon is becoming a crucial factor in the fight against climate change. But what exactly is embodied carbon, and why should the construction industry pay more attention to it?
Embodied carbon refers to all the carbon emissions that are associated with the production, transportation, and installation of construction materials. This includes the carbon impact of materials’ end-of-life stages. Essentially, the carbon emissions from these materials are “locked in” once the building is constructed, making embodied carbon a permanent part of the building’s environmental footprint.
In simpler terms, embodied carbon is everything outside of a building’s operational emissions. As buildings become more energy-efficient, the relative impact of embodied carbon will only grow. Additionally, most of the carbon emissions linked to a building are “front-loaded” in its lifecycle, meaning a large portion of the emissions occur during construction. This makes it vital to address embodied carbon now to have a meaningful impact on reducing overall emissions.
The Growing Importance of Regulations in Embodied Carbon Reduction
To combat the rising impact of embodied carbon, regulatory bodies are stepping in. In particular, California has emerged as a leader in developing laws that reduce embodied carbon in construction materials. These regulations not only aim to mitigate the environmental impact of construction but also help the industry meet its climate action goals.
New Regulations Driving Embodied Carbon Reduction in Construction
Buy Clean Legislation: A Step Toward Lower Emissions
One of the most effective strategies to tackle embodied carbon is through Buy Clean policies, which focus on procurement practices aimed at reducing emissions in construction materials. These policies target materials with the highest embodied carbon impacts, such as concrete, steel, and aluminum—together accounting for 23% of global emissions.
For example, the Buy Clean California Act (AB 262, 2017) mandates that public construction projects gather and disclose carbon emissions data through Environmental Product Declarations (EPDs). This legislation has not only helped reduce emissions but has also fostered a market for more sustainable construction materials. Other jurisdictions, including the federal government, have followed suit with similar Buy Clean initiatives.
Setting Carbon Intensity Limits
The Carbon Intensity of Construction and Building Materials Act (AB 2446, 2022) takes things a step further by setting specific carbon intensity reduction targets for various building materials. This law requires larger projects to submit lifecycle assessments and for manufacturers to produce EPDs, which document the carbon footprint of materials from production through end-of-life.
Embodied Carbon in the Building Code
In August 2023, California made another groundbreaking move by adopting new building codes that significantly reduce embodied carbon in buildings. The New Buildings Institute notes that California is the first state to address embodied carbon in public and private buildings larger than 100,000 square feet, and schools larger than 50,000 square feet.
These new code changes build on the Buy Clean California Act and offer flexibility by providing three compliance pathways:
- Building reuse – Retaining existing structures to minimize new materials and emissions.
- Prescriptive emission limits – Setting mandatory carbon emission limits for new buildings.
- Modeled reductions using lifecycle analysis – Calculating emissions reductions based on life cycle assessments of construction materials.
New Tools and Opportunities to Educate and Manage Risk
The pace of legislation in California provides a blueprint for other regions to follow as they seek to address embodied carbon in construction. It’s essential for professionals in the building industry to stay updated on the latest regulations.
A variety of industry-driven tools are emerging to support construction teams. For instance, the Embodied Carbon in Construction Calculator (EC3) is a free tool that enables benchmarking, assessment, and reductions of embodied carbon emissions in construction materials. Tools like EC3 allow construction teams to track their emissions and implement strategies to lower carbon impacts early in the supply chain.
How to Get Involved and Make a Difference
As building operations improve and embodied carbon becomes a larger percentage of overall emissions, it’s more important than ever to adopt strategies for reducing these emissions. From leveraging regulations like Buy Clean policies to utilizing tools like EC3, there are many ways the construction industry can contribute to a more sustainable future.
Want to reduce embodied carbon in your next project? Contact us to learn how our sustainability strategies can help you make a positive environmental impact while meeting your climate action goals.
Final Thoughts
As embodied carbon continues to gain attention, it’s crucial for industry professionals to stay informed and act. With new regulations and resources available, reducing embodied carbon is not just a possibility but a requirement for a sustainable construction future. By embracing these new tools and policies, we can make a significant difference in reducing the construction sector’s carbon footprint and advancing toward climate action goals.
Nicole DeNamur is an attorney and sustainability consultant, based in Seattle, WA. Her company, Sustainable Strategies, helps clients identify and manage the risks of sustainable innovation so they can pursue robust sustainability goals. She is also an award-winning contributing author and has developed and taught graduate-level courses at the University of Washington and Boston Architectural College. Nicole was named Educator of the Year by the International WELL Building Institute, and Sustainable Strategies hosts an online course, Accelerated WELL AP Exam Prep.
AIA Contract Documents has provided this article for general informational purposes only. The information provided is not legal opinion or legal advice and does not create an attorney-client relationship of any kind. This article is also not intended to provide guidance as to how project parties should interpret their specific contracts or resolve contract disputes, as those decisions will need to be made in consultation with legal counsel, insurance counsel, and other professionals, and based upon a multitude of factors.