Frequently Asked Questions

CarbonCure Technologies provides the concrete industry a platform for decarbonization, supporting sustainability and operational efficiency in concrete manufacturing through the use of our carbon mineralization technologies.

With its most widely deployed technology, CarbonCure Ready Mix, CarbonCure helps producers reduce the cement content of their concrete products by injecting captured carbon dioxide (CO₂) into concrete during mixing, where it converts to a solid mineral, calcium carbonate (CaCO₃). The mineralization of CO₂ improves the concrete’s microstructure and enables cement reductions while maintaining compressive strength and having no meaningful impact on fresh or hardened properties. CarbonCure Precast technology provides the same material savings benefit to precast producers. Carbon mineralized concrete produced with CarbonCure is fully compliant with ASTM C494 Type S requirements.

CarbonCure Reclaimed Water technology – currently in pilot deployments in Canada, France and Taiwan – bolts onto reclaimer tanks that collect plant wash water also known as slurry. The technology injects CO₂ to treat and stabilize cementitious solids suspended in the slurry and enables producers to put more of this reclaimed water back into their mixes. By using the technology, producers can reduce their use of virgin cementitious materials, freshwater and water treatment products, haul less waste offsite and lower the carbon footprint of their concrete products while delivering the same performance.

Visit our How it Works page to see CarbonCure’s technologies in action.

CarbonCure’ technologies are compatible with ready mix and precast producers supplying concrete to all project types, including residential, commercial and infrastructure. For ready mix plants using reclaimer tanks to collect wash water, CarbonCure’s reclaimed water technology bolts onto that system; CarbonCure’s technologies (flesh concrete CO2 injection and reclaimed water treatment) can be stacked/combined to achieve maximum operational efficiency.

CarbonCure taps into existing supply chains of CO₂, captured by industrial gas suppliers that have established sources, regional distribution networks and services in markets around the world. The CO₂ typically comes from the emissions generated during ethanol and ammonia production. To maximize benefits, CarbonCure is also actively working with industrial gas partners to expand the use of biogenic CO₂ sources, further increasing the ease of implementation.

The precise CO₂ dosage varies by the producer, materials and application. CarbonCure’s Customer Lab and Technical Services and Support (TSS) teams collaborate with each producer to evaluate the compatibility of our technologies with their materials and mix designs and the recommended dosage to optimize each mix.

Cement Reduction

Yes. CarbonCure enables producers to reduce cement content while maintaining concrete performance. The average cement content reduction is 4–5%, with the adjustment established for each mix design. Where mixes contain supplementary cementitious materials (SCMs), adjustments can reduce the total cementitious content.

Admixture Loading

Where admixtures are dosed based on cement, a reduced cement loading may reduce the quantity of admixtures required to achieve the same performance outcome. Comprehensive testing, extensive commercial use and customer feedback have indicated that CarbonCure is compatible with commonly used admixtures available on the market.

CarbonCure has been used in concretes with strengths up to C50/60. CarbonCure has been successfully proven in concrete applications with up to 10,000 – 14,000 psi (68.9 – 96.5 MPa).

CarbonCure is compatible with a broad range of cement types and supplementary cementitious materials (SCMs) such as fly ash and steel slag, successfully used across more than 20,000 mix designs to date. Most CarbonCure producer partners stack CarbonCure with other decarbonization strategies, including SCM optimization, cement reduction, and emerging low-carbon binders, to maximize cement efficiency, reduce embodied carbon, and improve material economics.

Yes. In the United States, CarbonCure was evaluated against ASTM C494 Type S and found to be compliant. In Canada, the CSA released A23.1 Annex S, which includes approval for adding CO₂ to concrete. For transportation projects, independent testing found that CarbonCure mixes performed similarly to control mixes and met or exceeded AASHTO M194 requirements, and CarbonCure also holds approvals in other markets around the world with commercial use across Asia, Europe, Latin America and the Middle East.

CarbonCure manages the heavy lifting. Our equipment is retrofitted into concrete plants, and CarbonCure field engineers work with plant staff to coordinate the installation from start to finish. The hardware and software can be installed in a day. Each system is designed to fit into an existing plant with minimal disruption. Once it’s in place, the system syncs with the plant’s batching software, so adding CO₂ to a mix is as easy as flipping a switch. From there, our team handles trial design, mix adjustment, reporting and field testing. Producers just need to collaborate for the initial mixes.

No. CarbonCure’s controlled CO₂ injections during concrete mixing is different from atmospheric carbonation of hardened concrete. Atmospheric carbonation can lower concrete alkalinity and compromise the protective layer around reinforcing steel when it reaches the reinforcement under conditions that support corrosion. In CarbonCure-treated fresh concrete, CO₂ reacts to form calcium carbonate, the mineral found in limestone. Academic concrete durability experts, such as Dr. Doug Hooton (University of Toronto) and Dr. Michael Thomas (University of New Brunswick), have conducted studies quantifying the pH of CO₂ mineralized ready mix concrete and concluded that there is no meaningful impact on pH and there is no potential for corroding rebar.

CarbonCure concrete is concrete produced using CarbonCure’s carbon mineralization technologies, which enable lower cement content while maintaining strength, quality and performance. Developers, designers and builders can specify and procure this lower-carbon concrete for construction projects.

CarbonCure’s technologies inject a precise dose of captured carbon dioxide (CO₂) into concrete during mixing. Immediately, the CO₂ chemically converts into a nano-scale calcium carbonate mineral and becomes permanently embedded in the concrete. The process improves the concrete’s microstructure, enabling concrete producers to reduce their cement content while maintaining strength.

On average, concrete produced with CarbonCure Ready Mix technology reduces 15-25 lb of CO₂ per cubic yard (7-11 kilograms of CO₂ saved per cubic meter). CarbonCure Precast technology saves 20-30 lb of CO₂ per cubic yard (12-18 kilograms of CO₂ per cubic meter). On average, that translates into 141 pounds of CO₂ (64 kilograms) kept out of the atmosphere with each truckload of CarbonCure concrete.

CarbonCure taps into existing supply chains of CO₂, captured by industrial gas suppliers that have established sources, regional distribution networks and services in markets around the world. The CO₂ typically comes from the emissions generated during ethanol and ammonia production. Industrial gas companies collect and purify this CO₂, with most of it consumed by the food and beverage industry.

No. The CO₂ remains embedded in the material. Carbon mineralization in fresh concrete is immediate and permanent with no risk of reversal. When injected by CarbonCure, the CO₂ instantly mineralizes, chemically bound as solid calcium carbonate rather than stored as a gas. Mineralization converts the CO₂ into nanosized calcium carbonate particles, the mineral found in limestone, rather than leaving gaseous CO₂ that can leak out.

Once injected into concrete, the CO₂ chemically converts into a calcium carbonate mineral that is permanently locked within the concrete. If that concrete structure is later demolished at the end of its life cycle, there is no risk of the mineralized CO₂ “leaking” or returning to the atmosphere as the CO₂ no longer exists.

The addition of CO₂ using CarbonCure’s technologies has no meaningful impact on the fresh properties of concrete – including workability or pumpability – or hardened properties – such as durability, density, pH, freeze-thaw, temperature, texture or color.

Please visit CarbonCure’s Resource Library for white papers, peer-reviewed studies and additional technical information.

CarbonCure concrete finishes the same way as conventional concrete, with an equivalent bleed rate and set time, so finishers can follow their normal practices. CarbonCure’s CO₂ injection process does not increase concrete mixer loading time or impact normal production operations, allowing producers to maintain existing throughput and batching practices. Once in use, CarbonCure concrete delivers the same finishing characteristics as conventional concrete, including equivalent bleed rates and set times, so contractors can place and finish concrete using their standard methods. Implementing CarbonCure also does not affect construction schedules, and the technology can typically be installed and commissioned at a new concrete plant in less than 30 days.

No. Carbon mineralization does not impact the long-term pH of concrete. When CarbonCure injects CO₂ into fresh concrete, the emissions instantly convert into tiny particles of limestone, calcium carbonate, which is an inert material. Third party studies quantifying the pH of CO₂ mineralized concrete have concluded that there is no meaningful impact on pH and there is no potential for corroding rebar.

The controlled insertion of precise dosages of CO₂ via CarbonCure’s carbon mineralization technologies is different than atmospheric carbonation, also known as weathering carbonation, of hardened concrete. Atmospheric carbonation in concrete occurs over the course of decades and can lower concrete alkalinity and, if it reaches reinforcing steel under conditions that support corrosion, compromise the steel’s protective passive layer. However, the two processes cannot be treated as interchangeable.

Concrete made with CarbonCure can be used in structural applications when the concrete mix meets the applicable building code, project specifications and approval requirements. In the United States, CarbonCure was evaluated against ASTM C494 Type S and found to be compliant. In Canada, CSA A23.1 Annex S includes approval for adding CO₂ to concrete. For transportation and infrastructure projects, concrete made with CarbonCure met or exceeded AASHTO M194 requirements in independent testing, and several state departments of transportation have added CarbonCure to their approved product lists. CarbonCure is also widely used in construction across North America, Latin America, APAC and EMEA and compatible with a broad range of cement types, admixtures and supplementary cementitious materials (SCMs), successfully used across more than 20,000 mix designs to date.

Yes. CarbonCure provides ready-to-use specification language. This includes recommended language for incorporating CarbonCure concrete into ready mix specifications and procurement policies. CarbonCure also offers a specification guidebook for design firms and a mix design submittal resource.

CarbonCure is available through a growing network of concrete producers worldwide, from Singapore to Saudi Arabia and from Vancouver Island to Florida.

See our Producer Map here.

Don’t see a local producer? Contact us. We’ll work with you and concrete producers in your region to help bring CarbonCure to your projects.

You can also support adoption through project specifications. In many regions, the biggest barrier is restrictive concrete specifications, such as minimum cement content requirements. CarbonCure works with architects, engineers, contractors, and producers to develop performance-based specifications that enable lower-carbon concrete without compromising strength or quality.

For guidelines on writing concrete specifications, visit our Specifications page.

CarbonCure can support embodied-carbon reduction strategies and documentation for LEED projects; using CarbonCure concrete does not automatically earn LEED points.

Project teams should use the requirements of their registered LEED version to determine eligibility and documentation.

LEED v5 puts embodied carbon at the center of Materials and Resources. Every project must now quantify the cradle-to-gate global warming potential (GWP) of its structure, enclosure and hardscape, including concrete, and identify its top three embodied carbon hotspots.

The Reduce Embodied Carbon credit then awards up to 6 points for demonstrated GWP reductions, with a whole-building life cycle assessment (WBLCA) as the path to the full 6 points and EPD-based options as alternatives.

Because concrete is among the largest contributors to structural embodied carbon, lower-carbon concrete is a direct lever.

CarbonCure producers can provide environmental product declarations (EPDs) for their mixes to support WBLCA and EPD-based calculations, and CarbonCure’s specification language supports verification of CO₂ mineralization from the producer.

The world’s building stock is expected to double by 2060. That’s like building another New York City every month and most of that will be concrete, the world’s most used building material. Concrete also has a hefty carbon footprint: Its key ingredient, cement, generates an estimated 7-8 percent of the world’s CO₂ emissions. That’s three times the carbon footprint of global aviation.

Carbon mineralization in concrete is an important component of an all-of-the-above climate strategy, reducing hard-to-abate emissions from this essential building material, to restore a healthy balance of carbon dioxide in the atmosphere and stabilize our climate.

CarbonCure is actively seeking opportunities to source atmospheric CO₂ for our concrete producer partners, as it becomes more readily available. This may include CO₂ from biogenic emissions or from emerging direct air capture (DAC) technologies. By deploying our carbon mineralization technologies, CarbonCure is effectively creating a larger market for atmospheric CO₂ supply and scaling carbon utilization pathways around the world.

Currently, CarbonCure taps into existing supply chains of CO₂, captured by industrial gas suppliers that have established sources, regional distribution networks and services in markets around the world. The CO₂ typically comes from the emissions generated during ethanol and ammonia production. Industrial gas companies collect and purify this CO₂, with most of it consumed by the food and beverage industry.

CarbonCure carbon credits are emissions reductions generated by mineralizing CO₂ in concrete through reductions of carbon-intensive cement in the concrete. Each credit is based on real-time production data, conservatively quantified against baseline concrete production, and independently audited and verified under a Verra methodology.

CarbonCure’s carbon credit program uses production data, lifecycle accounting and third-party verification to quantify CO₂ storage and emissions reductions. The calculation compares production with a baseline and accounts for emissions from the process itself. Production measurements and methodology assumptions inform the resulting estimates; independent auditors review the quantified benefits supporting credit issuance.

CarbonCure credits combine permanent CO₂ mineralization with measurable reductions in cement emissions. Unlike other project types that may have a high risk of over-crediting, non-additionality or reversal, CarbonCure’s technologies monitor every metric ton of CO₂ mineralized and reduced during concrete production, traceable to the specific plant and concrete batch using real-time telemetry built into each CarbonCure system operating around the world. In addition, unlike other project types, CarbonCure’s carbon storage and reduction benefits occur immediately, not years or decades from now.

Carbon mineralization in concrete is permanent with no risk of reversal. The CO₂ mineralized by CarbonCure is chemically bound as solid calcium carbonate rather than stored as a gas. It remains embedded in the concrete when a structure is demolished, or the concrete is crushed under normal end-of-life conditions. Mineralization converts the CO₂ into nanosized calcium carbonate particles, the mineral found in limestone, rather than leaving gaseous CO₂ that can leak out.

CarbonCure’s methodology (VM0043) has been approved by Verra under its Verified Carbon Standard (VCS), and its credits are listed on Verra’s registry as Verified Carbon Units (VCUs). Each VCU represents one metric ton of CO₂ reduced, and all issuance and retirement records are publicly available on the Verra Registry.

No. Credits work best as a complement to proactive strategies to reduce emissions, not a replacement. Carbon credits are one piece of the solution. CarbonCure’s Embodied Carbon Hub offers strategies for tackling Scope 3 emissions in building materials.

CarbonCure’s Carbon Products team can be reached at carboncredits@carboncure.com. You can also fill out the form on the Carbon Credits page to discuss your needs, whether that’s a spot purchase or a multi-year agreement.

Yes. CarbonCure offers both spot purchases and multi-year agreements. Contact the Carbon Products team to discuss options.