As Green Building Design Shifts Toward Embracing Embodied Carbon, Life Cycle Analyses Become More Crucial Than Ever
Professionals in the California construction industry are scratching their heads to understand the state’s new regulation around Life Cycle Assessment (LCA)s and embodied carbon. Effective July 1, 2024, California will be the first state in the U.S. to require the consideration of embodied carbon in order to comply with CALGreen, the Green Building Standards Code. The change will impact commercial projects exceeding 100,000 square feet and schools exceeding 50,000 square feet. These changes are the result of years-long efforts of academic education and global collaboration between AIA California, Rocky Mountain Institute, New Buildings Institute, USGBC, and other movements around the world, including EU Taxonomy. This article aims to provide an in-depth exploration of LCAs and embodied carbon.
It appears that the world is beginning to recognize the consequences of our wasteful energy practices and carefree, consumerism-driven lifestyle on our environment. The global discussion has now shifted to how to take responsibility for the environment we live in rather than simply being wasteful consumers. An LCA is used to assess the environmental impact of a product, considering both its material composition and our utilization of it. We must consider the following question in order to evaluate this environmental impact: Where does the product start its life?
In the past, there was a widespread view that as soon as we start using a product or building, we become responsible for its environmental effects. This led to the term “operational carbon,” which refers to the CO2 emissions stemming from the energy consumption needed to operate a building. It is now well acknowledged that the acquisition and processing of a resource or product entails several steps that contaminate the environment. 
As a result, an LCA is carried out to take into account a material’s whole life cycle, which includes all phases, from the extraction of raw materials to their disposal, such as manufacturing, transportation, installation, maintenance, and demolition. In the extensive and difficult estimate of environmental impact in the LCA methodology, two factors are considered. One divides the long road of the building life cycle into smaller segments, known as LCA stages, and the second considers several metrics for quantifying environmental consequences, known as environmental impact categories, which will be discussed further below.
In the context of buildings, an LCA involves assessing the environmental impacts associated with several stages such as constructing, operating, maintaining, and demolishing buildings. There are three different phases of the building life cycle that are considered for an LCA, denoted as A, B, and C, or “cradle-to-grave.” The A stages focus on raw material extraction, transportation to manufacturing, production processes, and site logistics. B stages highlight maintenance-related aspects, covering post-installation repair, replacement, and refurbishment. Finally, the C stages examine the end-of-life phase, assessing deconstruction, transportation to landfill, recycling, and/or reuse options for the product or system.
Given that building operations (27%) and embodied carbon from buildings (13%) collectively contribute to about 40% of annual global CO2 emissions, regulators and third-party platforms are increasingly prioritizing these areas.
Source: Kristin Hernandez and Sara Motamedi, Verdical Group
