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Pouring Concrete from Above

CarbonStar Rating System


The CarbonStar   Rating System is a technical specification for embodied carbon of concrete quantification & verification.


Setting the Standard

CarbonStar is designed to allow anyone, from governments and architects to contractors and roadbuilders, to quantify the embodied carbon of concrete. 

The standard provides minimum requirements and recommendations for the quantification and verification of the embodied carbon of a unit of concrete, including any carbon that is permanently sequestered during the production of the concrete or its input materials. The CarbonStar rating can be positive or even negative, in the case where more carbon is sequestered than emitted in its production.

The CarbonStar Rating represents the net embodied carbon in a unit of concrete. This calculation takes into account both the emitted and sequestered carbon per unit of concrete:

CO2CarbonStar = CO2Emitted - CO2Sequestered

The CarbonStar Rating is the embodied carbon of concrete in mass of CO2 per unit of concrete. But in order to reach that figure, the CO2 sequestered in mass-per-unit of concrete must also be calculated.

To learn more about the CarbonStar Technical Specification CSA SPE-112:21, please click the button to the right to get to the official page. 

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