When Should You Document?
From July 1 2025, nearly all new construction must document A4 and A5 emissions under BR18. Only unheated buildings under 50 m² and certain extensions under 250 m² on single-family homes are exempt. The limit is 1.5 kg CO₂e/m²/year (or 1.1 kg for the low-emission class). This guide is your quick reference for when to log — and when to skip.
This guide covers the rules. See "Getting started with A45" for a full platform walkthrough.
A4 — Transport
Material Transport
All permanent building materials listed in BR18 Annex 2 Table 6 must be documented. Transport from factory/warehouse to the construction site is A4.
Rule of thumb: if it's on the drawings and stays in the building, document it.
Exceptions — What You Can Skip
- Small parts below the threshold (nails, screws, sealants, membranes per Table 6)
- Temporary/auxiliary materials not part of the finished building
- Materials lost or damaged during transport (not documented)
Equipment Transport — The 1-Ton Rule
- Under 1 ton: SKIP — fully exempt (both transport and fuel)
- Over 1 ton: MUST document (cranes, excavators, scaffolding, site cabins)
The 1-ton threshold applies to the equipment's own weight, not the cargo weight.
Unsure about a material? Check BR18 Annex 2 Table 6 on bygningsreglementet.dk.
A5 — Construction Site
Energy Consumption (Electricity, Heating, Fuel)
On-site energy consumption must be documented with actual measured data — standard values are not allowed for energy.
- Includes: electricity, heating, diesel for machinery over 1 ton
- Exempt: machinery under 1 ton, terrain work outside the building footprint
Construction Waste
Actual weights per fraction must be documented (15 BR18 fractions) via weighing slips. Alternatively, you can use the EPD method if you have environmental product declarations for the materials.
- NOT: household waste, canteen waste, soil
If waste is mixed (multiple fractions in one container), you must use the emission factor for the fraction with the highest value.
Soil Removal
- Excess/contaminated soil related to the building = document
- General terrain outside the building = skip
Standard Values
Not everything requires actual data. Here's the overview:
- Waste transport + soil transport: CAN use standard values (0.06 kg CO₂e/m²/year each, from Table 10.2)
- Energy: MUST be actual data
- Waste fractions: actual kg required, but Table 11 factors can be used for conversion
Quick Checklist
Use the table below as a quick reference for the most common situations.
| Situation | Document? | Reason |
|---|---|---|
| Concrete delivery for foundation | Yes | Permanent building material (Table 6) |
| Nails, screws, sealant | No | Below threshold (Table 6) |
| Mobile crane (8 tons) | Yes | Equipment over 1 ton |
| Power drill (15 kg) | No | Equipment under 1 ton |
| On-site electricity | Yes | A5 energy — actual consumption required |
| Diesel for mini excavator (<1 t) | No | Machine under 1 ton — fully exempt |
| Wood waste from rafters | Yes | Construction waste — weighing slip per fraction |
| Canteen waste | No | Not construction waste |
| Excess soil from excavation | Yes | Soil removal related to the building |
| Terrain outside the building | No | Outside the building footprint |
Documentation Methods in A45
A45 supports multiple methods, depending on what data you have available:
| Method | Used for | You must provide |
|---|---|---|
| A4 — Measured fuel | Material transport | Litres diesel/petrol, fuel type |
| A4 — Measured distance | Material transport | Km, weight, vehicle type |
| A4 — Standard value | Material transport | Material type, weight |
| A4 — Equipment transport | Equipment over 1 ton | Km, weight, vehicle type |
| A5 — Energy consumption | Electricity, heating, fuel | kWh/litres, energy source |
| A5 — Waste transport | Construction waste | Kg per fraction (or standard value) |
| A5 — Soil transport | Soil removal | Tonnes of soil (or standard value) |
See "Getting started with A45" for a step-by-step walkthrough of each method.
Sources and Further Reading
This guide is based on the current BR18 regulations. We recommend reading the official sources as well:
- BR18 Climate Requirements (§ 297-298) — The official climate calculation requirements in the Danish Building Regulations: bygningsreglementet.dk
- VCBK Guide: The Construction Process from July 1, 2025 — Practical guide from the Danish Housing Authority on the new climate requirements for the construction process: Download PDF
- BR18 Annex 2 Table 6 — Overview of building materials that must be included in the climate calculation: Table 6
This guide is for informational purposes only and does not replace the official regulations. For the applicable requirements, always refer to the BR18 Building Regulations. A45 assumes no liability for decisions made based on this guide.
Frequently asked questions
No. Hand tools weigh under 1 ton and are fully exempt from both transport and fuel documentation.
Use the A4 standard value method (based on material type and weight) or the A4 measured fuel method (if you have consumption data).
No. Only permanent parts of the building must be documented. Temporary structures (formwork, temporary walls) are exempt.
No. Standard values are only allowed for certain items (waste transport, soil transport). On-site energy consumption must always be actual measured data.
You can technically document retroactively, but at project completion you must have the full picture. Best practice: log each delivery/event as it happens throughout construction — it's far easier than reconstructing months of data at the end.
Table 6 is available on bygningsreglementet.dk: [Table 6](https://www.bygningsreglementet.dk/bilag/b2/bilag_2/tabel_6/)