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.