CO2 Footprint vs EPD: What’s the Difference?
CO2 footprint or EPD — both terms are important when evaluating the environmental impact of building materials. But what is the difference, and how can you compare them correctly? Let’s break it down.
What Is an EPD?
EPD stands for Environmental Product Declaration. It is a standardized document that provides verified information about the environmental impact of a construction product.
Manufacturers can voluntarily develop an EPD, and it must be verified by an independent third party to ensure accuracy and reliability. In countries such as Belgium (B-EPD), EPDs are also used as a legal basis for sustainability claims.
An EPD goes beyond just the CO2 footprint. It assesses 16 environmental impact categories, including:
- Global Warming Potential (GWP / Carbon footprint)
- Water use
- Soil acidification
- Eutrophication
- Fossil resource use
- Land use
EPDs evaluate the entire life cycle of a product — from raw material extraction to disposal (cradle-to-grave).
How to Compare EPDs?
EPDs are often country-specific and may follow different rules or standards. For example, Belgium uses B-EPDs, accessible through government databases.
Because methodologies can differ across countries and Program Operators, EPDs are not always directly comparable.
Important Comparison Principle
Products must be compared based on the same functional performance.
For example, when comparing PIR insulation and mineral wool:
- PIR may require 80 mm thickness
- Mineral wool may require 130 mm thickness
To ensure fairness, comparisons should be made based on the same thermal resistance (R-value), not simply by product unit.
CO2 Footprint vs Environmental Footprint
Product CO2 Footprint (Carbon Footprint)
A product CO2 footprint measures the total greenhouse gas (GHG) emissions caused by a product throughout its life cycle.
Although called a “carbon” footprint, it includes multiple greenhouse gases (e.g., methane, nitrous oxide), expressed in CO2 equivalents (CO2e).
It focuses solely on the impact of climate change.
Product Environmental Footprint (LCA)
A Product Environmental Footprint is based on a Life Cycle Assessment (LCA). It evaluates all relevant environmental impacts — not just climate change.
An LCA typically measures 15+ environmental impact categories, providing a complete environmental performance profile.
How Companies Use Product Footprints
Uses of Product CO2 Footprints
- Carbon impact reporting and marketing transparency
- Carbon offsetting initiatives
- Compliance with carbon taxes and emissions trading schemes
Uses of Product Environmental Footprints
- Environmental Product Declarations (EPDs)
- EU Product Environmental Footprint (PEF) framework
- Environmental Cost Indicator calculations
- Sustainable product design improvements
Environmental footprints help identify where impacts originate and which categories require improvement.
How to Calculate CO2 and Environmental Footprints
1. Calculating a CO2 Footprint
- Perform a full LCA and report only climate impacts
- Use a carbon footprint calculator aligned with GHG Protocol or ISO standards
Ensure calculators follow recognized standards such as:
- GHG Protocol Product Standard
- ISO 14040 / ISO 14044
- PAS 2050
2. Calculating an Environmental Footprint (LCA)
The only scientifically accepted method is Life Cycle Assessment (LCA), following ISO 14040 and ISO 14044.
Using specialized LCA software simplifies data collection and impact modeling.
How to Get Started with LCA (4 Steps)
- Define your objective: Determine scope, responsibility, budget, and timeline.
- Check applicable rules: Identify relevant PCRs or certification requirements.
- Collect life cycle data: Materials, energy use, emissions, and transport data.
- Calculate impacts: Use LCA tools to model environmental impacts.
LCAs provide a complete picture of environmental performance, supporting informed sustainability decisions.
Conclusion
In summary, a CO2 footprint focuses only on climate change impacts, while an EPD — based on a full LCA — provides a comprehensive environmental performance profile across multiple impact categories.
EPDs are developed under strict standards, independently verified, and governed by Program Operators to ensure transparency, credibility, and comparability.
For construction products and sustainable procurement, EPDs offer a more complete and reliable decision-making tool.
