Developers are placing carbon requirements on suppliers in the form of Environmental Product Declarations, embodied carbon limits written into procurement contracts, and third-party verification of carbon performance data. These requirements apply most directly to concrete and structural materials, where embodied carbon is highest and the data is now expected to be product-specific and independently verified. The sections below address the most common questions concrete manufacturers and precast producers are encountering from their developer clients.
What types of carbon data are developers now requiring from suppliers?
Developers now require suppliers to provide Environmental Product Declarations (EPDs) as the baseline carbon data format. An EPD is a standardised document that quantifies the greenhouse gas emissions associated with a product across its lifecycle, expressed in kilograms of CO₂ equivalent per unit of material. Beyond EPDs, developers are increasingly requesting product-specific carbon data rather than industry-average figures, along with documentation of the methodology used to calculate it.
The shift from generic to product-specific data reflects a broader change in how embodied carbon is being managed at the project level. Developers and their design teams are using carbon calculation tools that require actual product figures to produce credible whole-building assessments. Industry-average EPD values, while acceptable in some contexts, are losing ground in procurement processes where carbon performance is a differentiating factor.
Concrete manufacturers should expect requests for the following types of carbon documentation:
- Product-specific EPDs verified by an accredited third party
- Declared unit carbon footprint figures aligned with relevant EN or ISO standards
- Documentation of the system boundary used in the EPD calculation
- Evidence of carbon storage or carbon removal if claimed as part of the product footprint
- Data formatted for compatibility with common whole-life carbon assessment tools
Where carbon storage is claimed, for example in concrete products where CO₂ has been mineralised into the material during production, developers and their verifiers want to see the methodology behind the claim. Permanent storage needs to be distinguished from temporary carbon sequestration, and the documentation must show that the stored carbon will not be re-released.
Why are embodied carbon limits appearing in procurement contracts?
Embodied carbon limits are appearing in procurement contracts because developers face growing pressure from investors, planning authorities, and corporate net-zero commitments to reduce the carbon footprint of the buildings they construct. Operational energy has been addressed through building regulations for years, but embodied carbon, the emissions locked into the materials themselves, has historically been unregulated and unmeasured. That gap is now closing through voluntary procurement requirements and, in some markets, mandatory policy.
Several converging factors are driving this change. Large institutional investors and real estate funds are applying carbon screening criteria to development projects as part of environmental, social, and governance frameworks. Planning authorities in cities including London, Amsterdam, and Helsinki have introduced or are piloting embodied carbon reporting requirements as a condition of planning consent. Corporate occupiers are specifying low-carbon buildings as part of their own scope 3 emissions reduction strategies, which creates a direct commercial incentive for developers to pass those requirements down the supply chain.
For concrete and precast suppliers, this means embodied carbon is moving from a marketing conversation to a contractual one. Suppliers who cannot provide the required carbon documentation risk being excluded from tender processes regardless of price or delivery performance. The requirement is not primarily about achieving a specific number at this stage, though thresholds are becoming more common. It is primarily about demonstrating that the data exists, is credible, and can be verified.
How do developers verify that suppliers meet carbon targets?
Developers verify that suppliers meet carbon targets primarily by requiring third-party verified EPDs and by conducting or commissioning independent whole-life carbon assessments at the design and procurement stage. Verification relies on the supplier providing documentation that an accredited certification body has reviewed, rather than self-declared figures. At the project level, verification is typically carried out by a carbon consultant or structural engineer using recognised assessment frameworks.
The verification process generally works in two stages. The first stage happens during procurement: suppliers submit EPDs or equivalent carbon documentation, which the developer’s team checks for scope, methodology, and certification status. EPDs that have been independently verified against EN 15804 or equivalent standards carry more weight than unverified declarations.
The second stage can occur during or after construction, particularly on projects where carbon targets are tied to planning conditions or green building certifications. In these cases, the developer may require as-built carbon data confirming that the materials used matched what was specified. This creates a need for suppliers to maintain traceability between their production records and the carbon figures they have declared.
Where carbon credits or carbon removal credits are claimed as part of a product’s footprint, the verification standard is higher still. Developers and their advisors look for credits that are independently certified under recognised schemes, with clear evidence of permanence, additionality, and quantification. Mineralised CO₂ in concrete products, for example, needs to be supported by gas flux measurement data and laboratory verification, not just a supplier’s assertion.
What carbon thresholds are commonly set for concrete and building materials?
Carbon thresholds for concrete and building materials vary by project type, geography, and the framework being applied, but the general direction is toward progressively tighter limits over time. In procurement terms, thresholds are most commonly expressed as a maximum global warming potential per functional unit, such as kilograms of CO₂ equivalent per cubic metre of concrete or per tonne of structural steel. There is no single universal standard, but several frameworks are establishing reference points that are becoming widely referenced.
Green building certification schemes such as BREEAM and LEED award credits for achieving embodied carbon reductions relative to a baseline, which effectively creates a soft threshold. Developers pursuing high certification levels select materials with lower carbon footprints to accumulate those credits. This creates indirect market pressure on suppliers even where no hard contractual limit exists.
Some public sector clients and planning authorities are moving toward harder limits. These typically reference benchmark figures derived from industry EPD databases, with procurement requirements set at a percentage below the benchmark. Concrete products face particular scrutiny because concrete is used in large volumes and Portland cement, the primary binder in conventional concrete, carries a high carbon intensity per tonne.
For precast concrete specifically, the declared carbon footprint of conventional products using standard Portland cement mixes sits considerably higher than products made with alternative binder combinations or CO₂ mineralisation processes. Developers setting thresholds are increasingly aware of this range and are using it to frame their requirements. Suppliers who can demonstrate product-level carbon footprints well below the conventional benchmark are in a stronger position when thresholds are applied.
How can concrete suppliers realistically meet developer carbon demands?
Concrete suppliers can meet developer carbon demands through a combination of cement content reduction, use of Supplementary Cementitious Materials (SCMs) such as slag or fly ash, and CO₂ mineralisation during curing. These approaches are not mutually exclusive. The most effective path for precast producers is to combine several methods to achieve a product-level carbon footprint that is both documentable and credible, then to capture that performance in a verified EPD.
Cement reduction is the most direct lever available to most producers. Portland cement accounts for the largest share of embodied carbon in conventional concrete. Replacing a portion of the cement with SCMs such as ground granulated blast furnace slag reduces the carbon intensity of the binder. The challenge is that reducing cement content without other interventions can affect early-age strength development, which matters particularly in precast production where products need to reach demoulding strength within a fixed cycle time.
CO₂ mineralisation during the curing phase addresses this challenge directly. When CO₂ is introduced into the curing chamber at the right concentration and timing, it accelerates early-age strength development through a seeding mechanism, which means cement content can be reduced without sacrificing production throughput. At the same time, the CO₂ is permanently mineralised into the concrete structure as carbonates, reducing the net carbon footprint of the finished product. When combined with SCMs such as steel slag, which can be activated by CO₂ in ways that are not possible in conventional curing, the carbon footprint reduction can be substantial.
Meeting developer carbon demands also requires the right documentation infrastructure. Achieving a lower carbon footprint in production is only half the task. Suppliers need to be able to demonstrate it with data that developers and their verifiers will accept. This means maintaining production records, linking them to EPD calculations, and in some cases providing carbon credit documentation for the CO₂ stored in products.
The Carbonaide CO₂ Curing System and the Carbonaide Service Platform address both the production and documentation sides of this challenge. The system manages CO₂ flow during curing with precision instrumentation, while the platform centralises carbon data, supports EPD calculations with product-specific figures, and provides full carbon storage documentation including independent verification and certification. For precast producers looking to respond to developer procurement requirements with credible, verified carbon performance data, this combination of hardware and software provides the operational foundation to do so.
How Carbonaide helps concrete suppliers respond to developer carbon requirements
Carbonaide provides precast concrete producers with the tools to reduce product-level carbon footprints and document those reductions in a format that meets developer procurement requirements. The solution covers both the production process and the data management needed for compliance.
- Cement content reduction: The CO₂ curing process enables producers to reduce Portland cement content by using CO₂ to accelerate early-age strength development, maintaining production cycle times without excess cement.
- CO₂ mineralisation: CO₂ introduced during curing is permanently stored in the concrete as carbonate minerals, reducing the net carbon footprint of finished products and enabling negative emission claims where binder composition allows.
- Product-specific carbon data: The Carbonaide Service Platform measures and records CO₂ mineralisation per chamber and per product batch, providing the product-specific data needed to update EPD calculations.
- Carbon credit documentation: The platform’s premium version provides full carbon storage documentation including independent verification and certification of carbon removal credits, supporting suppliers whose developer clients require verified carbon offset evidence.
- Compatibility with existing facilities: The Carbonaide CO₂ Curing System can be retrofitted to existing curing chambers, meaning producers do not need to build new facilities to meet carbon procurement requirements.
