
As the built environment continues to grow and change with our societal needs, the environmental impact of construction projects must be considered to ensure sustainable infrastructure growth. One way to demonstrate a building project’s environmental impact is through certifications, the foremost of which is Leadership in Energy and Environmental Design (LEED) certification.
In order to achieve LEED certification, a construction project must abide by certain criteria meant to standardize the quantification and reduction of a project’s overall environmental impact. The LEED system, as regulated by the United States Green Building Council (USGBC) and Canada Green Building Council (CAGBC), has evolved through several versions since its inception in the 1990s.
LEED v5, the newest version of LEED’s guidelines, went through two rounds of public comment in 2024 and is expected to open for registration in early 2025. When developing LEED v5, three central impact areas were prioritized: decarbonization, quality of life, and ecological conservation and restoration. As a result, the forthcoming LEED v5 guidelines are some of the most far-reaching yet, promising to deliver on sustainability and innovation.
The priority areas of LEED v5 are echoed in updated prerequisites and credits. One notable area of improvement when comparing LEED v5 to its predecessor is the inclusion of embodied carbon as a major sustainability quantifier. Material selection is now codified in a new Materials and Resources prerequisite, as well as an embodied carbon-focused credit.
The “Assess and Quantify Embodied Carbon” prerequisite has been developed as part of LEED v5 to encourage the assessment and quantification of the materials used in the project. The goal of this assessment is to encourage the knowledge and reduction of embodied carbon, the carbon dioxide emissions that result from the manufacturing and processing of building materials.
The “Reduce Embodied Carbon” credit is a new addition to the credit to the LEED v5 credit library. With up to six points available, embodied carbon is given significant weight in the new LEED system. This credit utilizes global warming potential (GWP) as quantified in environmental product declarations (EPDs) to quantify the environmental impact of the materials used in a new construction project.
CarbiCrete’s innovative technology enables the production of concrete products without using cement. The products utilize an industrial byproduct, steel slag, as a binding agent and are cured via carbon mineralization, leading to the permanent sequestration of CO2 within the end-product. This combination of emissions avoidance and carbon dioxide removal, when quantified in an EPD, reduces the GWP of a concrete masonry units (CMU) by over 90%, to just 11.7 kg CO2e per m3 of concrete. Compared to CarbiCrete’s impact toward achieving LEED v4.1 certification, CarbiCrete can make an even greater impact under the LEED v5 framework.
One of the requirements that must be complied with to receive points under the new “Reduce Embodied Carbon” credit is the identification and reduction of the top sources of embodied carbon predicted in the project. With cement-based concrete often serving as a major emissions source in new construction projects, incorporating new technologies like CarbiCrete’s is one way to achieve the six possible points in this credit and work toward LEED certification of a project under the updated requirements of the v5 framework.