EPDs in Steel 101 (Part 3): How to Use an Environmental Product Declaration (EPD)

Environmental Product Declarations (EPDs) in Steel: Part 3

In this third installment of the EPDs in Steel series, we will explore how to use an EPD to implement sustainable practices and meet regulatory requirements for projects in construction, infrastructure, energy, transportation and other industries that utilize steel. As established in EPD articles Part 1 and Part 2, this information can be used to interpret cradle-to-gate Type III verified EPDs aligned with ISO 14025 and 21930 under the North American Product Category Rule (PCR) for Designated Steel Construction Products.

Knowing how to read an EPD is essential in specifying steel in the design phase and ensuring the product meets sustainability, performance and project requirements.

Why are EPDs Important in the Steel Industry?

Understanding how to use an environmental product declaration ensures transparency and credibility in material selection. Type III EPDs provide standardized, third party-verified data on a product’s environmental impact so that engineers, designers and construction professionals can make informed, responsible choices.

Beyond regulatory compliance, EPDs serve as valuable tools for conveying sustainability data to stakeholders, including clients, investors and project teams. By illustrating a product’s life cycle impacts, such as carbon footprint, resource use and emissions, EPDs enable professionals to align material selection with broader sustainability objectives. Since these documents target an external audience, they reinforce industry credibility by ensuring verified data supports environmental claims.

For engineers and construction professionals, understanding EPDs improves the ability to design effective structures while meeting performance and environmental standards. By incorporating EPD analysis into the specification process, professionals can contribute to more sustainable construction practices and strengthen the industry’s commitment to transparency and environmental responsibility.

How to Use a Steel EPD in Material Decision-Making

Type III steel EPDs empower construction professionals to make informed decisions about what materials they specify for a project by evaluating the environmental impact of those materials with reliable data. EPDs provide a clear understanding of a product’s life cycle assessment (LCA) impacts, which enables architects, engineers and procurement teams to select steel that meets performance and sustainability goals, contributing to sustainable supply chain management and environmental management systems.

Assessing the carbon footprint of steel products enables project teams to make more responsible material choices that help reduce emissions and support broader environmental objectives. This is particularly important for projects seeking green building certifications like LEED (Leadership in Energy and Environmental Design), where integrating EPD data contributes to earning sustainability credits.

For example:
Steel manufactured using an electric arc furnace (EAF) with scrap metal as its primary input is less emissions-intensive than steel manufactured with blast furnace-basic oxygen furnace (BF-BOF) processes (read more about the two ways to make steel). In addition, EAF steel products generally have lower emissions than others, depending on factors like recycled content and energy inputs. An EPD uses verified data to validate greenhouse gas (GHG) emissions and other environmental impacts to help identify the most sustainable steel materials.

Incorporating EPDs into the material selection process ensures transparency, accountability, and alignment with sustainability initiatives, ultimately driving more responsible construction practices and reducing the long-term environmental impact of built structures.

Various construction professionals use EPDs to ensure informed decisions and compliance, including the following:

• Steel manufacturers can showcase product transparency and dedication to environmental responsibility.
• Architects and designers can select materials that align with the project’s sustainability goals, green building certifications like LEED, and project performance requirements
• Engineers can analyze the data to compare structural materials based on environmental impact, durability, and efficiency while meeting design specifications.
• Contractors and builders can refer to EPDs when sourcing materials to comply with project specifications and requirements.
• Procurement and supply chain professionals can ensure project materials meet environmental standards for government and private-sector projects with strict sustainability criteria.
• Developers and owners can assess the long-term environmental impact of building materials and support sustainable investment strategies.
• Regulatory bodies and certifiers can use EPD data to verify compliance with green building certifications and government sustainability regulations.

Common Pitfalls and Misinterpretations in EPDs

One common mistake is failing to distinguish between industry-average EPDs and product-specific EPDs. Industry averages offer a general benchmark but do not reflect the environmental impact of a specific manufacturer’s product. Relying solely on industry averages can lead to inaccurate comparisons, especially when project sustainability goals require precise data on material sourcing and production processes.

As an example, a product-specific EPD is only directly comparable to equivalent product-specific EPDs of the same type, such as rebar to rebar, but not rebar to hollow structural sections (HSS) or another steel product.

Learn more about specific environmental product declaration types in EPDs Part 1 and see more about analyzing and comparing EPDs in EPDs Part 2.

Keep in mind that most product EPDs are based on a cradle-to-gate scope, which includes the impact from raw material extraction or scrap processing until the product leaves the manufacturing facility. Therefore, regional differences can play a critical role in interpreting EPDs. Factors such as energy grids, transportation distances and local manufacturing practices can significantly affect environmental impact. Sometimes, manufacturers publish facility-specific EPDs to capture environmental data for a product made at one location compared to another, so consider location-specific data within project requirements.

Best Practices to Interpret Steel EPDs

When comparing EPDs, remember to avoid using them as direct comparison tools between different material types, such as steel and wood or various types of concrete. The underlying LCA methodologies, data assumptions and functional unit can vary significantly between material types, making direct comparisons misleading. For example, steel products are often listed with a functional unit of one metric ton, while concrete uses one cubic meter – this alone makes the EPD results between these two materials incomparable. Instead, EPDs should be used to evaluate environmental impacts within the same material category; for example, only a steel reinforcing bar EPD should be compared against other steel reinforcing bar EPDs.

Additionally, material selection should consider the longevity and durability of the final structure. A material with a lower initial carbon footprint may not be the most sustainable long-term choice if it requires frequent maintenance or replacement. Factoring in the structural longevity and lifecycle impact of materials like low-embodied carbon steel ensures a more accurate and responsible sustainability assessment.

By understanding these nuances, construction professionals can avoid misinterpretations and use EPDs more effectively to drive informed, sustainable material choices.

Nucor manufactures low-embodied carbon steel using EAF technology and publishes verified Type III EPDs to deliver transparency and help industry professionals make informed decisions.

The Sustainable Steel Specification Writing Guide is a resource to help engineers and designers use EPDs to specify sustainable steel in the design phase of construction projects.

If you are unsure how to interpret or compare EPDs, consult with our steel industry experts to make the most informed product decisions based on accurate data. Contact Nucor Construction Solutions