The GCCA Global Ratings for Cement are the implementation of the numerical definitions introduced by the GCCA at COP29 in November 2024 and categorise cement products based on Global Warming Potential (GWP), measured in embodied carbon dioxide equivalent per tonne of cement (ECO₂e/t).
Indications are that some countries will choose to only adopt concrete ratings rather than cement ratings, as concrete is the final product. This approach aligns with the thinking behind the GCCA roadmap to achieving net-zero concrete which is a whole life roadmap.
Ratings – description
The GCCA low carbon cement ratings are expressed in units of embodied carbon dioxide equivalent per tonne of cement product (ECO2e /t).
The ratings are divided into seven bands (AA to F):
| Rating | Description |
|---|---|
| AA | Near Zero Emissions Cement – based on the decarbonisation of cement in the GCCA Global Roadmap to net zero |
| A – F | Equally spaced carbon footprint values define the ratings – built on the IEA low-emission definitions for cement production |
Countries choose a clinker/cement ratio (one-off choice) and use the detailed Low Carbon Ratings for Cement graph below, to calculate rating values. An example is presented here for which the chosen clinker/cement ratio is 0.706. This is the value adopted by Germany who developed their VDZ carbon class in parallel with GCCA.
Ratings – derivation
The cement ratings are based on the decarbonisation of cement in the GCCA Global Roadmap to net zero and build on the IEA methodology developed for cement.
The ratings are the implementation of the numerical definitions introduced by the GCCA in COP 29 in November 2024.
Classifying a product
To determine a product’s rating:
- A manufacturer calculates the product GWP in accordance with EPD methodology.
- GWP is compared with country ratings.
A type-III EPD is by definition a third party verified document, meaning that a producer can simply rate their products based on the GWP value.
Note that countries may have specific certification or labelling provisions. In Germany, VDZ has a cement carbon class labelling method. This was developed in parallel and is fully aligned to GCCA.
EPD methodology / Country adaptation
The GCCA ratings use the following EPD methodology, the most widely used globally:
- Standards: EN 15804+A2, PCR-001 – Cement and building lime (EN 16908)
- Database: ecoinvent
- Scope: cradle-to-gate (A1-A3)
- “Net GWP”: Emissions from treated waste accounting as per ISO 21930 and EN 15804+A2 (some countries, contrary to the standards, choose to account for emissions from treated waste and report gross GWP)
If a country has different EPD custom and practice GCCA has already, or will, work with the national association to develop national adapted ratings. Manufacturers can then calculate GWP using the country EPD custom and practice.
