Construction site carbon vs building carbon
two indicators, two tools
RE2020 distinguishes building carbon (material footprint, FDES/INIES) from construction site carbon (construction phase footprint, items A4-A9). Both contribute to the overall carbon assessment, but they cover different scopes and require different tools.
Why the distinction matters
Under RE2020, a building's carbon footprint is broken down into several indicators. The two main ones for the construction phase:
Building carbon (Ic construction)
Carbon footprint of the building's materials and components, calculated from FDES (Environmental and Health Declaration Sheets) and the INIES database.
Scope: construction products, technical equipment, architectural works
Construction site carbon (Ic site)
Carbon footprint of the construction phase itself: transport, machinery, waste, site facilities, personnel travel. Items A4 to A9 per EN 15978.
Scope: site activity, not the materials
Confusion between these two indicators is common. A developer who claims "we have reduced the carbon of our project by 15%" may be referring to building carbon (choice of bio-sourced materials), construction site carbon (logistics optimisation), or both. Without distinguishing the scopes, the claim is not verifiable, and after 27 September 2026, it could constitute an unlawful environmental claim under Directive 2024/825.
Comparison table
| Criterion | Building carbon (Ic construction) | Construction site carbon (Efficarbone) |
|---|---|---|
| Scope | Materials, components, equipment | Site activity (transport, machinery, waste, site facilities) |
| Nomenclature | Modules A1-A3 (production) + B-C (use, end of life) | Modules A4-A9 (transport + construction site) |
| Data sources | FDES, INIES, PEP, manufacturer data | ADEME Base Empreinte, invoices, site records |
| Calculation tools | LCA software (Elodie, ClimaWin, Perrenoud...) | Efficarbone |
| Project phase | Design (specifications, tender documents, detailed design) | Tender, detailed design, execution (pre-assessment to actual assessment) |
| Key stakeholder | Thermal / LCA engineering consultancy | Project owner (client side) |
| RE2020 | Mandatory, regulatory thresholds | Lump-sum value by default, replaceable by actual measurement |
The RE2020 lever: actual measurement vs lump-sum value
RE2020 uses lump-sum values for construction site carbon when no actual measurement is available. These values are intentionally conservative: they penalise the building's overall carbon assessment. When a project owner actually measures their construction site carbon with Efficarbone, they can replace the lump-sum value with the actual measurement in the RE2020 calculation.
This lever becomes increasingly powerful as RE2020 carbon thresholds tighten: milestones in 2025, 2028 and 2031. For a building that is close to the threshold, replacing the lump-sum value with an actual measurement (often lower if the site is well managed) can make the difference between compliance and non-compliance.
Read the full details of the RE2020 measurement vs lump-sum mechanism →
Frequently asked questions
Construction site carbon covers modules A4 (transport of materials to site) and A5 (site emissions: energy, waste, temporary installations) per EN 15978. Modules A1-A3 (material manufacturing) fall under component carbon.
Yes. The EVO 25.05 standard from Effinature includes the construction site component for renovation projects. Modules A4-A5 apply regardless of the project type, with adaptations for demolition and management of existing waste.
Efficarbone relies on actual site data: delivery notes (A4), energy consumption records (A5), waste tracking slips (A5). This primary data replaces lump-sum values and produces a traceable assessment.
Measure your construction site carbon with Efficarbone
Replace RE2020 lump-sum values with actual measurements. Items A4-A9, ADEME factors, full traceability for every project.