Low Embodied Carbon (LEC) Standards

Choosing Glass Products,
Environment & Ecology,
Science of Glass

What is Embodied Carbon? 

While energy efficiency and operational carbon are important aspects of eco-friendly building designs, embodied carbon emissions continue to gain traction as a major focus in today’s sustainable design landscape. 

Generally, architects have begun to favor products that are low in embodied carbon, a term that refers to emissions caused by the manufacturing and installation of construction materials. In measuring the embodied carbon in building products, including glass, the accepted metric is Global Warming Potential (GWP), which is expressed in kilograms of equivalent carbon dioxide referred to as CO2-eq.

Previously, there was no standard for “low embodied carbon” building products, and manufacturers were able to market their products as “lower embodied carbon” when applicable based on subjective interpretations of what could be considered “good” embodied carbon content.

Today, embodied carbon emissions are a principal issue, particularly with increasing initiatives and legislation focused on reducing carbon in materials used for building projects. For example, as the largest purchaser in the world, the U.S. Federal Government’s Federal Buy Clean Initiative was established to promote the use and development of low-carbon, made-in-America construction materials.

United States Low Embodied Carbon Standards

In establishing best practices for the U.S. building products industry, standards were set for low embodied carbon (LEC) products by the Inflation Reduction Act of 2022 and the U.S. General Services Administration (GSA). To meet this standard, a product must offer a Type III EPD and contain an “Acceptable” embodied carbon content that is less than 1,401 kilograms of CO2 equivalent (kg CO2e).

By these standards, LEC products can fall into three different product categories according to embodied carbon content:

Product Category

Embodied Carbon Content


1,401-1,371 kg CO2e


1,371-1,332 kg CO2e

Most Preferred

< 1,331 kg CO2e

Based on Vitro’s latest certified Flat Glass EPD, which reported an embodied carbon content of 1,240 kg CO2e, all Vitro Architectural Glass products meet the GSA’s Top 20% Low Embodied Carbon (LEC) material category. This designation applied to all Vitro-produced architectural glass from all Vitro plants all the time.

Glass is one of four building products for which the GSA has leveled LEC standards, and while other types of products may need to sacrifice quality to achieve LEC status, the composition, characteristics, clarity and strength of glass can remain the same.

Glass manufacturers employ carbon reduction measures, including the increased use of recycled cullet and energy-efficient Oxy-Fuel technology, to improve energy efficiency in the glass production process without altering the composition, characteristics, clarity and strength of glass products.

Finding Information on Embodied Carbon

Information on a building product’s embodied carbon content and GWP can be found in an Environmental Product Declaration (EPD). An EPD is a detailed, third-party certified report of the energy use and emissions surrounding the manufacturing of a product—in addition to the packaging extraction, transportation and processing of related raw materials. With increasing focus on embodied carbon, GWP is what the industry uses to assess the extent to which the life of a product impacts the environment.

EPD Image_

EPDs are a particularly useful tool that can be used to demonstrate a product’s compliance with legislation and standards codes. For more information on EPDs, see “Understanding EPDs.” To download EPDs for Vitro’s flat and processed glass products, see “Sustainability Documentation.”

For information about Vitro’s commitment to sustainable products and practices, please visit vitroglazings.com/sustainability. For any other glass questions, please contact Vitro Glass or call 1-855-VTRO-GLS (1-855-887-6457).