Spotlight on Sustainability

An environmental product declaration (EPD) is a document describing the environmental impacts of a product such as a concrete mix, structural steel, or even architectural products such as carpet. EPDs are used by designers, owners, and regulators to compare products and determine the impact of a project. They also provide the information necessary to complete a Life Cycle Analysis (LCA), which is becoming more and more common.

They should be generated per ISO 14040/14044, ISO 14025, EN 15804, or ISO 21930 standards. ISO 14025 ensures verification by a third party, is very common, and often required. The data is collected and calculated according to standardized Product Category Rules defined in ISO 14025. EPDs are generally valid for 5 years from creation.

There are two main types of EPDs: Industry Average and Product Specific. An Industry Average Type III EPD is developed by industry organizations (AISC, NRMCA, etc.) and represents an aggregated environmental impact of the respective material, while a Product Specific Type III EPD is developed by a specific material manufacturer (Nucor, Vulcan, etc.) and measures the environmental impact of a single product.

The most basic information in an EPD is the global warming potential (GWP), measured in kilograms of CO2-equivalent (kg-CO2eq). This puts a number to the embodied carbon that can be allocated to a particular product. Whole Building Life Cycle Analyses, such as those now required by LEED v5, will also track additional impact categories that have other effects on the environment.

A great resource to find published EPDs in the DMV area is the Embodied Carbon in Construction Calculator (EC3) by Building Transparency. For more information, please reach out to any member of the SEA-MW Sustainable Design Committee.

LEED v5 was launched in April 2025 and will become mandatory for all new projects seeking LEED certification starting July 1, 2026. While LEED v5 introduces many changes across categories, one of the most significant shifts is the increased emphasis on embodied carbon.

The most impactful change for structural engineers is that an embodied carbon assessment is now required for all LEED certification levels. At a minimum, projects must complete a cradle‑to‑gate (A1–A3) life‑cycle assessment (LCA). Under LEED v4, performing an LCA was optional and worth a point on its own. Under LEED v5, no points are awarded simply for completing an LCA. It’s now a baseline requirement. Under LEED v5, embodied carbon reductions contribute meaningfully to LEED scoring. Points are awarded based on the percent reduction in global warming potential (GWP) relative to a baseline “reference building” defined using ASCE’s Whole‑Building Life‑Cycle Assessment methodology:

2 points – Meets baseline

3 points – 10% reduction

4 points – 20% reduction (required for LEED Platinum)

5 points – 30% reduction

6 points – 40% or greater reduction

These changes to LEED are expected to push more project teams to adopt detailed LCA’s and proactive embodied carbon strategies, with an increased focus on structural systems and material selection. Preparing now will position us to better support our clients and remain competitive as embodied carbon becomes a central driver of sustainable design under LEED v5.

For more information, please reach out to the SEA-MW Sustainable Design Committee.

It’s no secret that buildings account for 40% of global greenhouse emissions; 28% from building operations and 12% from embodied carbon in materials. Yet, while many decarbonization efforts have been implemented in reducing operational carbon through energy-efficient design, embodied carbon is often overlooked. Embodied carbon refers to the CO₂ emissions associated with the extraction, manufacture, transportation, and installation of building materials. Once construction is complete, these emissions are effectively locked in, meaning we, as structural engineers, have lost our ability to reduce emissions further.

The materials we specify influence not only building performance but also environmental and human health at both global and local scales. Engaging in meaningful discussions about structural systems and material choices early in the design process, alongside the entire project team, can help identify opportunities to reduce embodied carbon. By addressing it from the outset, embodied carbon can become a key performance metric rather than an afterthought.

For more information on how you can help drive the conversation around embodied reduction on your projects, reach out to any member of the Sustainable Design Committee. Want to learn more? Get started with SE 2050 Committee’s Resources Working Group “Top 10 Things Every Structural Engineer Should Know.”