How to Comply with California's New Embodied Carbon Requirements: A Summary Guide to the CALGreen Code

California is leading the way in reducing the environmental impact of the built environment. As of July 1, 2024, the state's CALGreen Code, or California Green Building Standards Code, requires new construction, alterations, and additions to comply with updated embodied carbon requirements. Intended to reduce greenhouse gas emissions that result from the construction process — including material sourcing, manufacturing, maintenance, and disposal — these new requirements are part of the nation’s first-ever mandatory green building standards code.  

In this blog, we explore some of the most frequently asked questions about the CALGreen Code, including how industries will be impacted and when. We also discuss three pathways for understanding and achieving compliance under the new CALGreen requirements.

What is embodied carbon?

Embodied carbon — also known as embodied greenhouse gas (GHG) emissions — is defined by the United States Environmental Protection Agency (EPA) as the amount of GHG emissions associated with the “upstream stages of a product’s life.” This includes extraction of raw materials, production, transport, and manufacturing. The EPA reports that the industrial sector is “linked to nearly a third of annual U.S. GHG emissions, and the manufacturing of construction materials and products accounts for 15% of annual global GHG emissions.”

By taking significant strides to manage and reduce embodied carbon from the construction and building sectors, the CALGreen Code will help mitigate climate change while contributing to California’s goal of achieving carbon neutrality by 2045.

Which industries are impacted by CALGreen?

The new CALGreen Code significantly impacts the construction and building sectors and focuses on new construction, alterations, and additions.

The official CALGreen website explains, “CALGreen is a mandatory green building code with additional voluntary provisions,” and these latest requirements “encourage sustainable construction practices” in five topic areas:

• Planning and design
• Energy efficiency
• Water efficiency and conservation
• Material conservation and resource efficiency
• Environmental quality

More specifically, CALGreen includes mandatory measures that apply statewide to both residential and non-residential projects and will require new construction, alterations, and additions over 100,000 square feet to comply with new embodied carbon requirements. These requirements also apply to K-12 schools that are 50,000 square feet or larger. The threshold for non-residential buildings will decrease to 50,000 square feet.

We've included some examples of residential structures that are required to comply with CALGreen:

• Hotels, motels, lodging houses
• Apartment houses, condominiums
• One and two-family dwellings, townhouses, factory-built housing
• Dormitories, shelters for unhoused persons, congregate residences, employee housing
• Other types of dwellings containing sleeping accommodations with or without common toilets or cooking facilities 

What does the original CALGreen code include?

In 2010, the California Green Building Standards Code or CALGreen Code was established, marking the first-ever statewide green building code in the United States. The original CALGreen Code focused on reducing water use, improving indoor air quality, and conserving energy. The CALGreen Code has been updated numerous times since its initial drafting.

According to California’s Department of Housing & Community Development, the revised CALGreen Code applies to the “planning, design, operation, construction, use, and occupancy of every newly-constructed building or structure on a statewide basis unless otherwise indicated.  Additions and alterations to existing buildings which increase the building’s conditioned area, interior volume, or size are also covered by the scope of CALGreen.” For reference, the full CALGreen Code is available here: California Code of Regulations, title 24, part 11.

 Three Pathways for Compliance | What needs to be done and by when?  

The latest revision to the CALGreen Code became effective on July 1, 2024, and will remain in effect until December 31, 2025. The new CALGreen Code offers three options for reducing embodied carbon in your building project: Building Reuse, Whole Building Life Cycle Assessment (WBLCA), and Environmental Product Declarations (EPDs). You can choose the option that best suits your design, budget, and goals. Below, we walk through each of these three pathways.

Building Reuse

Building reuse (see section 5.105.2, worksheet WS-3) requires that at least 45% of the existing building's primary structural elements and enclosure be reused. Primary structural elements include foundations, columns, beams, walls, floors, and lateral elements. This option is ideal for renovation or adaptive reuse projects that preserve the existing building fabric and minimize the need for new materials. (Exceptions to this pathway are outlined in section A5.105 of the CALGreen Code.) For this method to be documented, Worksheet WS-3 must be completed with all calculations clearly recorded.  

Whole Building Life Cycle Assessment (WBLCA)

A WBLCA requires calculating the environmental impacts of a building throughout its life cycle, from cradle-to-gate, in accordance with the ISO 14044 standard. This analysis allows for optimized building design and conscientious material choices based on a comprehensive analysis of their impacts. The WBLCA (see section 5.409.2, worksheet WS-4) option requires demonstration of a 10% reduction in global warming potential (GWP) compared to a baseline building. GWP is a measure of how much a material or activity contributes to climate change over a given time.  

Under CALGreen, Tiers 1 and 2 bring additional voluntary compliance for building material conservation and resource efficiency. If adopted by a city, county, or city and county, Tier 1 or 2 projects of any size require either a 10-15% or 15-20% GWP reduction, respectively, in terms of baseline WBLCA. For documentation of WBLCA, Worksheet WS-4 must be completed. Depending on the circumstances of each building project, Worksheet WS-9 “may be required by the enforcing entity to demonstrate compliance with the requirements.” (See pg. 5-15 of the CALGreen Code.) Organizations interested in learning more can reference CALGreen Appendix A5.409.1 to A5.409.5 along with the 2024 CALGreen Update handout from California’s Department of General Services.

Environmental Product Declarations (EPDs)

The third option, known as the Prescriptive Path, offers a streamlined method focused on fewer but more impactful materials. Each permanently installed material listed in CALGreen’s table 5.409.3 must be accompanied by a Type III Environmental Product Declaration (EPD). These declarations — based on life cycle assessment studies that are third-party verified  — provide either product-specific and often factory-specific Global Warming Potential (GWP) data.  

Table 5.409.3 shows the Maximum Acceptable ‘cradle-to-gate' GWP value for each pertinent product. Given the prescriptive nature of this pathway, compliance with these thresholds is mandatory. These limits are set at 175% of the industry-wide EPD’s GWP value, ensuring that only materials with the lowest carbon footprints are utilized.

SCS Global Services provides both LCA services for EPDs and independent verification of LCA reports and EPDs. The SCS EPD program was developed in 2011 and is one of the largest repositories of EPDs in North America.  

What additional components are included as part of the CALGreen Code?

Besides embodied carbon requirements, the new CALGreen Code also includes two other components that aim to improve the sustainability and resilience of buildings.  

Electric Vehicle (EV) Charging

Under the latest update to the CALGreen Code (see section 4.106.8), new construction of multifamily dwellings, hotels, and motels must equip 40% of the total number of parking spaces with Level 2 electric vehicle charging receptacles (EV Ready). This will help encourage the adoption of electric vehicles and reduce the emissions from transportation.

Certified Wood Component

According to section ‘A5.405 - Material Sources’ of the CALGreen Code, certified wood components that meet certain sustainability standards fall under the Code’s greater regional and bio-based materials requirements. CALGreen emphasizes that projects must provide wood products for “at least 50% of the project’s permanently installed products” — and that these products must be labeled and certified as having been produced in compliance with “the accepted principles of sustainable forest management.”

CALGreen specifies six different sustainable wood certifications allowed under the Code’s revision — and construction projects must comply with one or more:

• Sustainable Forestry Initiative (SFI)  
• Forest Stewardship Council (FSC)
• Program for the Endorsement of Forest Certification (PEFC)  
• American Forest Foundation’s American Tree Farm System® (ATFS)  
• Canadian Standards Association’s Sustainable Forest Management System Standards (CSA Z809).
• Lastly, the certified sustainable wood product manufacturer's fiber sourcing process must have been audited by an approved agency and be deemed compliant with the ASTM D7612 standards for responsible or certified source of wood. 

SCS Global Services is here to help

For 40 years, SCS Global Services has served as a trusted partner in third-party environmental and sustainability certification, auditing, testing, and standards development. As a leader in life cycle assessment (LCA), sustainable wood certifications, and EPDs, SCS offers decades of experience providing solutions for the green building industry. Our teams provide expertise in all major certifications underpinning the green building sector, such as Forest Stewardship Council (FSC) Sustainable Forestry Initiative (SFI), SFI Chain of Custody, PEFC Chain of Custody, EPDs, HPDs, Indoor Air Quality, among many others.

If you are interested in learning more about our services and how we can help your company navigate the CALGreen Code, please contact us at [email protected]. For additional information on Environmental Product Declarations and Life Cycle Assessments, please contact the Environmental Certification Team here or reach out to our Forestry Management Certification Team by emailing: [email protected].