Uncovering Embodied Carbon in EPDs

Written by Lauren Breckenridge, LEED AP , Sustainability Associate at Green Badger

The construction industry is under increasing pressure to reduce its carbon footprint. A significant portion of the total carbon emissions of a building comes from the materials used. To make informed decisions about material selection and achieve carbon reduction goals, understanding and quantifying embodied carbon is essential. Environmental Product Declarations (EPDs) provide valuable data on a product’s environmental impact, including its embodied carbon footprint. If you are an AEC professional it is your time to shine by specifying and procuring products that will help create sustainable buildings for future generations.

What is Embodied Carbon

You may be wondering what embodied carbon entails. Embodied carbon refers to the carbon dioxide emissions associated with the production, transportation, and disposal of a material or product. We often measure it in kilograms of carbon dioxide equivalent (kgCO2e) per unit of material. By understanding the embodied carbon of different materials, construction professionals can make informed decisions to reduce the overall carbon footprint of a building.

First things first, you need an EPD

Where to find an EPD

Green Badger makes it easy to find EPDs for the products you want to use in your project. By using the advanced search option in Green Badger you are able to find products that specifically have EPDs whether that be for option 1 and/or option 2. Products that meet the criteria for EPD option 2 display an embodied carbon reduction. For a deeper understanding of how to read EPDs, refer to our ebook, Guide to EPD and MIR: Options 1 & 2.?

Green Badger also has an ebook LEED Product Guide that provides a list of products that have EPDs. With using the product guide ebook you can browse for products that have EPDs by product type.

Prioritizing High-Impact Materials

To effectively reduce a building’s embodied carbon, focus on materials with the largest carbon footprint. Key materials include:

Concrete: One of the most widely used construction materials, concrete’s embodied carbon largely depends on the type of cement used and aggregate sources. Opting for lower-carbon cement blends or incorporating supplementary cementitious materials (SCMs) like fly ash or slag can significantly reduce emissions.

Steel: Another essential material, steel’s embodied carbon varies based on production methods and recycled content. Choosing high-recycled content steel or exploring alternative structural systems can mitigate carbon impacts.

Timber: Timber products, particularly those sourced sustainably, often have lower embodied carbon due to carbon sequestration during growth. Using certified wood products and managing forests responsibly can enhance sustainability credentials.

Insulation and Other Materials: Materials such as insulation, glass, and plastics also contribute to embodied carbon. Selecting products with lower manufacturing emissions and longer lifespans can reduce overall environmental impact.

Setting Project Goals?

By utilizing the EC3 calculator, you can establish reduction goals for each CSI division. This can be found by entering your product criteria i.e. structural steel, hot-rolled sections, recycled content etc. into the EC3 search tool. This will return results for all the EPDs in their database and provide a box and whiskers plot that will give an achievable GWP target for that product category. Once you have set your goals and identified the materials with the highest embodied carbon impact, it is important to communicate these goals to your project team and suppliers.?

How to find the Global Warming Potential number

There are two ways to find the Global Warming Potential (GWP) number either on the EPD or with the EC3 calculator tool. The first way we will delve into is directly on the EPD. One you have your product’s EPD you will need to find the section stating the LCIA Results and locate the Global Warming Potential number (GWP). This is the number you will want to use to compare similar products with.?

Directly on the EPD: Look for the GWP number within the LCIA results section of the EPD as shown above.

Another way to find this number is by using the EC3 calculator tool. By inputting the necessary data into the EC3 calculator, you can easily determine the Global Warming Potential number of a product. This information is crucial for setting realistic targets for the materials you are procuring.

Using the EC3 Calculator: Input your search criteria into the EC3 calculator and open the EPD in the calculator to locate the GWP number.

It is important to note that simply opening EPDs and comparing them side by side is a challenging way for identifying the best product to meet your embodied carbon goals, as there are many variations within a product type. We recommend using the EC3 calculator tool and entering your search parameters to ensure you are comparing products with similar features.

By understanding embodied carbon and taking steps to reduce it, the construction industry can significantly contribute to mitigating climate change. By focusing on high-impact materials, setting clear goals, and utilizing tools like EC3 and Green Badger, AEC professionals can make informed decisions. Embracing sustainable practices and advocating for low-carbon products is essential for building a greener future. Let’s work together to create a more sustainable built environment.