MACF: A Comprehensive Guide for Construction Companies on the Carbon Border Adjustment Mechanism
Key Takeaways
- The MACFentered its final phase on January 1, 2026: European importers must purchase certificates proportional to the emissions embedded in certain imported goods.
- Six industrial sectors are affected: cement, iron and steel, aluminum, electricity, fertilizers, and hydrogen. The construction industry is directly exposed due to its reliance on materials with high CO₂ content.
- Starting in 2028, the European Commission plans to expand the scheme to include 180 downstream products (finished and semi-finished), which will significantly increase the scale of the impact on the construction sector.
- The lack of reliable data exposes operators to punitive default values—this is the trap of the “imposed tax base.”
- Solutions such asDecarbo’Solution® enable players in the construction industry to structure their approach, measure their carbon footprint, and manage their exposure.
Contents
What is the MACF, and why is it relevant to the construction industry?
The MACF — the carbon border adjustment mechanism, known in English as CBAM (Carbon Border Adjustment) Mechanism) — is a European regulation stemming from the Green Deal.
Its goal: to prevent “leakage” that occurs when goods manufactured in third countries with less stringent climate standards enter the EU market at a lower cost. The European Commission has implemented this mechanism to ensure that EU industry is not penalized by the climate transition.
Why is the construction industry on the front lines?
Because the construction industry consumes large quantities of materials with a high environmental impact: steel, cement, and aluminum. These three categories have been included in the scope of the program since January 1, 2026.
In France, the building and public works sector accounts for approximately 23% of national greenhouse gas emissions. The production of hydraulic cement contributes 2.9% to this total, and the production of structural steel generates between 1.8 and 2.4 metric tons of CO₂ per unit produced. Given these figures, this pricing has a major impact on the local industry’s procurement costs.
For a long time, CO₂ remained a secondary indicator in the construction industry—useful for CSR reporting, but rarely a deciding factor in financial decisions. This framework is a game-changer: it transforms environmental considerations into a cost variable comparable to a tariff. For procurement departments and CFOs, the implementation of this regulatory framework represents a paradigm shift.
Which products and sectors are targeted?
The six categories covered since 2026
The measure applies to the flow of six categories of goods originating in third countries:
- Cement — Its production emits approximately 656 kg of CO₂ per metric ton. Imported clinker is a particular focus.
- Iron and Steel — Reinforcement, framing, and metal structures: these are at the heart of construction.
- Aluminum — Window and door frames, building facades, ventilation equipment. The intensity can reach 9.7 tCO₂e per metric ton produced.
- Electricity supplied from outside the Union.
- Nitrogen Fertilizers
- Hydrogen
Did you know?
- These six sectors alone account for 45% of industrial emissions in the EU. But a major turning point is on the horizon for 2028: in December 2025 (COM 2025/0419), the Commission proposed expanding the scope to 180 downstream products —finished and semi-finished goods containing steel or aluminum. Construction equipment, prefabricated structures, and building electrical systems would be directly affected.
Two levels of exposure for the industry
Large corporations that import directly from third countries become “authorized declarants ”: they must register, report the CO₂ content of their purchases, and acquire the corresponding credits.
SMEs and mid-sized companies in the sector are indirectly affected: the additional costs are passed down the entire supply chain. Without proper planning, profit margins could be severely squeezed in both the public and private construction markets.
How It Works: Certificates, Allowances, and Emissions Calculation
Timeline, Transition Period, and Registration
The regulation is being implemented gradually, in parallel with the phase-out of free allowances under the EU ETS:
- October 2023 – December 2025 : Transition period. Operators were required to report the CO₂ emissions from their purchases, with no financial obligations. This period allowed member states to prepare for the implementation of the registry.
- January 2026 : Transition to the final phase. Mandatory registration in the national registry, annual reporting, and acquisition of securities.
- May 2027 : First securities redemption, covering the 2026 issues.
- ~2028 : Planned extension to downstream assets, subject to a final vote in Parliament and the Council.
- 2026–2034 : Phased elimination of free allowances, which increases the cost of the program.
How does the system actually work?
Each authorized importer must purchase certificates proportional to the CO₂ embodied in goods imported into the Union. The unit price is indexed to the average price of EU ETS allowances. This requirement applies to shipments originating from countries outside Europe.
Warning
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The price of European emission allowances rose from an average of €73 per metric ton in 2025 to a record high of €88.31 per metric ton in early 2026. The trend is structurally bullish as free allocations decline. This increase directly amplifies the impact on import costs.
If a local tax has already been paid in the state of production, the operator may deduct that amount from the number of certificates to be surrendered. During the transitional period, no certificates were required. Since 2026, the amount has been based on a quarterly average of the allowance price. Default values apply when actual data from the manufacturer is not available.
Assessment of the CO₂ Embedded in Imported Goods
For each imported shipment, the embedded emissions must be determined: direct production emissions (Scope 1), emissions related to energy consumption (Scope 2), and the composition of the product (inputs, industrial processes). This determination is based on data provided by the manufacturer in the third country—a complex process when the production chain spans multiple jurisdictions. The ratio in metric tons of CO₂ per unit of product forms the basis of the MACF declaration.
Financial Impact on the Construction Industry
Specific additional costs to be factored into budgets
Let’s look at a specific example. A company that purchases 10, 000 metric tons of steel from Turkey, with a carbon intensity of 2 metric tons of CO₂ per metric ton, will have to purchase allowances worth 1.5 to 1.8 million euros per year at current prices. This cost will increase as free EU ETS allowances are phased out.
For imported cement, with approximately 0.65 tCO₂ per metric ton of clinker, the additional cost amounts to 48 to 57 € per metric ton of product. When considered in terms of the volumes involved in a large-scale construction project, this cost becomes a significant budget item for the construction sector.
Did you know?
- France produces approximately 16 million metric tons of binder each year , generating nearly 10 MtCO₂e. Clinker purchases, although a minority, are steadily increasing. The regulation specifically aims to restore a level playing field between European manufacturers (subject to the EU ETS) and goods imported from third countries.
The Trap of the Imposed Tax Base: When a Lack of Data Comes at a High Cost
When an operator is unable to obtain specific data from its suppliers, it is forced to use default values calculated based on the most polluting sites in the sector. The discrepancy between these values and reality can amount to tens or even hundreds of euros per unit.
Warning
- This phenomenon has a name: “imposed tax base.” The operator no longer controls its tax base—it is simply subject to it. And the financial penalty directly impacts gross margin and EBITDA, not a CSR report. It is a purely financial risk that can be managed by the CFO’s office.
Data Quality: A Top Financial Priority
Beyond the price of allowances and volumes, the real adjustment variable is the quality of supplier information (PCF – Product Carbon Footprint). A finance department can manage this risk using three metrics: the coverage rate for specific data, the PCF quality score, and the rate of reliance on default values. The goal: to rapidly reduce the tax base for the most exposed items.
2028: Expansion into downstream products—a strategic shift
A New Scale for Construction
Until now, the system has covered only raw materials: steel coils, aluminum profiles, and clinker. With the proposed expansion to downstream goods (COM 2025/0419), embedded CO₂ will also be accounted for in finished and semi-finished products: engines, chassis, machined parts, construction equipment, and prefabricated modules.
Definition
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The downstream goods arefinished or semi-finished products that incorporate materials covered by the MACF. The system will track the environmental content throughout the value chain: from the foundry to the module delivered to the construction site. The operator introducing the finished product must obtain the corresponding certificates.
For construction companies, this expansiondirectly affects imported construction equipment, prefabricated metal modules, industrial hardware, and building electrical systems.
From climate climate reporting
Extending the system to downstream goods transforms it into a carbon pricing tool. It is no longer a matter of customs compliance; it is a cost line that impacts profitability. Two construction companies may purchase the same equipment at the same supplier price and yet incur very different additional costs —depending on whether one has structured its data and the other has not. The adjustment is determined by the quality of the reporting and the traceability of emission values.
"Current" PCF vs. "CFO-grade" PCF: The Difference That Matters
In the post-2028 context, simply having a number isn’t enough. You need a number that can be defended—one that is verifiable, documented, traceable, and reproducible. That’s the difference between a CSR indicator and data that can be used as evidence during a customs inspection.
Generic approaches (sector averages, proxies) provide a starting point, but become unreliable when tax implications are involved.My-PCF®,Decarbo’Solution®’s assessment solution, enables the production of auditable PCFs that comply with European regulations.
The schedule works against latecomers
Even though the expansion is scheduled for 2028, preparations must begin now. Three timeframes overlap:
- Supplier lead time : Obtaining robust, documented data takes 12 to 24 months per wave
- Methodology : Standardizing a consistent estimation method across an entire procurement portfolio cannot be done on the fly
- Finance Timeline : CFOs need budget visibility before the invoice becomes due
Did you know?
- Waiting until 2027 to prepare means, in most cases, accepting a default tax base —and thus being subject to excessive taxation. Starting now allows you to pay the legal minimum and protect your profitability.
Requirements and Regulations for the Industry
For direct filers: registration and filing
Any company that imports goods covered by the regulation into the Union must:
- Register with the competent authority as an authorized declarant
- Submit an annual report (by May 31) detailing the CO₂ content of the previous year’s flows
- Acquire and return securities corresponding to the reported volume
- Document the verification method with a verifiable audit trail
After the 2028 expansion, the complexity will increase: the information will need to cover multi-tiered manufacturing chains overseas, creating a chain of documentation in which each link must provide usable data.
For parties indirectly exposed
SMEs and mid-sized companies in the construction industry that do not import directly are nonetheless feeling the impact of rising prices for materials and equipment. For these organizations, the challenge is to:
- Understanding the environmental origins of their purchases
- Measure their GHG footprint, particularly Scope 3
- Identify ways to reduce emissions: less resource-intensive suppliers, alternative materials, short supply chains
- Incorporate the CO₂ factor into their responses to requests for proposals
Definition
- The Scope 3 covers indirect emissions related to the value chain —material purchases, freight, upstream subcontracting, and downstream use of structures. In the construction industry, Scope 3 emissions often account for more than 70% of the total.
Coordination with Other European Climate Regulations
The system does not operate in isolation. It is part of a convergent regulatory framework: the CSRD (non-financial ), RE2020 (thresholds for new buildings in France), the European Green Taxonomy, and the SNBC (a target of a 40% reduction in GHG emissions in the real estate sector by 2030). Together, these initiatives are moving in the same direction: making the cost of CO₂ visible, measurable, and manageable for the entire sector.
Practical Guide: How to Prepare?
Step 1: Map Your Import Flows
Identify the goods and materials in question within your supply chain. What volumes are imported? From which sources? Through which suppliers? Looking ahead to 2028, which finished products contain materials covered by the regulations? This mapping of imports forms the foundation of any effort to ensure compliance with the regulations.
Step 2: Measure Your Footprint
Conducting a comprehensive GHG inventory, including Scope 3, is essential for identifying the areas most at risk. Decarbo’Solution® enables construction professionals to manage this process in a structured manner, in compliance with ISO 14064 and GHG Protocol standards .
Step 3: Obtain Defensible Data
The system relies on the quality of supplier information. A usable PCF must be verifiable, documented, traceable, and reproducible. My-PCF® enables the generation of this type of auditable data. Decarbo’Supply® complements this approach by enabling portfolio management: prioritizing high-risk items, comparing performance, and reducing the carbon footprint.
Step 4: Enter into contracts with suppliers
Environmental information must become a progressive contractual provision in relations with non-EU partners. Decarbo’Tender® enables the widespread adoption of this process: PCF clauses in requests for proposals, update requirements, and performance-based incentive/penalty mechanisms.
Step 5: Develop a Reduction Plan
Beyond compliance, the challenge is to develop a credible decarbonization plan. Simulate supply scenarios and set targets aligned with the Paris Agreement and the SBTi’s pathways SBTi —that’s what Decarbo’Target®, the trajectory module of Decarbo’Solution®.
Did you know?
- The “hotspots” method is the most effective: focus data collection efforts on the 20% of items that account for 80% of the risk, then gradually expand. However, the PCF must be of “CFO-grade” quality from the outset—even within a limited scope.
Turning Climate Challenges into Opportunities
The MACF is not merely an administrative formality. It is a regulation that places a real and increasing price on the CO₂ embedded in goods imported into the European market. For the construction industry, the impact will be structural—all the more so with the planned extension to downstream goods in 2028, which will significantly broaden the scope of the regulation.
The question is no longer“Should we be concerned about this issue? ” but “Have we structured our supplier data and our capacity to calculate emissions? ” Those who have organized their data collection and recording will pay a fair price. The others will be subject to the default tax base and the additional costs associated with the transition.
Decarbo’Solution® supports construction professionals in this transition with a comprehensive suite of solutions: calculation of auditable carbon footprints (My-PCF®), supplier management (Decarbo’Supply®), contract management (Decarbo’Tender®), and low-carbon trajectory planning (Decarbo’Target®).
Warning
- The first certificate submission will take place in May 2027 for the 2026 data sets. Improving the quality of supplier data takes 12 to 24 months. Every month lost increases the risk of falling back on costly default values.
Controlling your data means controlling your bill. Don't just react to the MACF—anticipate it.