The CO₂ limit (CO₂-grænseværdi) is the maximum carbon footprint that a new Danish building may have under building regulations BR18. It is expressed in kg CO₂-equivalents per m² of heated floor area per year and must be documented through a life cycle assessment (LCA).
Why does it matter to you?
If you’re building a development over 1,000 m², it’s a legal requirement. But the threshold is tightening and is expected to apply to increasingly smaller buildings — driving material choices and construction methods in a greener direction.
Even as a private homeowner planning a smaller project, it’s worth knowing the threshold — requirements may reach your project within a few years, and CO₂ documentation is becoming a competitive differentiator.
The thresholds in practice
| Period | Threshold | Applies to |
|---|---|---|
| From 2023 | 12 kg CO₂-eq/m²/year | New buildings > 1,000 m² |
| From 2025 | 10 kg CO₂-eq/m²/year | New buildings > 1,000 m² |
| Future | Extension to smaller buildings | Expected |
The thresholds primarily cover modules A1–A5 in the LCA standard (material production and construction process), not operational energy consumption.
How to comply
To stay within the threshold, the developer must:
- Carry out an LCA calculation (e.g. using LCAbyg)
- Choose materials with low EPD-documented GWP values
- Minimise concrete use or choose low-carbon cement
- Consider timber and recycled materials
Frequently asked questions
Does the CO₂ limit apply to my private home?
Not yet, if it’s under 1,000 m². But the threshold is expected to be extended. Many consultants already recommend calculating CO₂ for all projects.
Does operational energy count towards the limit?
No. The CO₂ limit covers “embodied carbon” — CO₂ from material production and the construction process. Operational energy is regulated separately through the energy frame.
What happens if I exceed the threshold?
Planning permission may be refused or granted with conditions requiring design changes. Exceeding the limit may require compensating measures in the project.