Commercial & Industrial Energy Rating
What is it?
A Section J Report (contained within Volume 1 of the NCC) focuses specifically on Energy Efficiency. It sets the “minimum legal floor” for performance. Unlike the SDA, which is about “best practice” and “holistic sustainability,” Section J is a strict pass/fail technical audit of the building’s thermal envelope and services.
The Part J Breakdown (NCC 2022)
The report is divided into several “Parts,” each targeting a specific area of the building. In the latest NCC 2022 update, these parts are:
| Part | Focus Area | What the report checks |
| J1 | Building Fabric | Insulation levels in roofs, walls, and floors. It calculates Total R-Values. |
| J2 | Glazing | Solar Heat Gain Coefficient (SHGC) and U-Value of windows to prevent overheating. |
| J3 | Building Sealing | Requirements for seals on doors, windows, and fans to stop air leakage. |
| J4 | Air-Conditioning | Efficiency of HVAC systems and plant equipment (chillers, pumps, etc.). |
| J5 | Ventilation | Power consumption of fans and outdoor air requirements. |
| J6 | Lighting & Power | Maximum “Watts per square metre” allowed for lights and control sensors. |
| J7 | Heated Water | Efficiency of hot water systems and insulation of pipes. |
| J8 | Facilities for Monitoring | Requirements for energy meters to track usage (critical for larger buildings). |
| J9 | Renewable Energy/EV | New in 2022: Solar PV readiness and EV charging infrastructure. |
The Two Pathways to Compliance
When you commission a Section J report, the consultant will use one of two methods:
A. Deemed-to-Satisfy (DtS)
- The “Checklist” Approach: The most common and cheapest method.
- How it works: You simply meet the specific numbers listed in the code (e.g., “Wall insulation must be R2.5”).
- The Downside: It’s very rigid. If one window is too big, the whole report might “Fail,” forcing you to use expensive high-performance glass.
B. JV3 Verification (Performance Solution)
- The “Computer Modelling” Approach: A sophisticated 3D thermal simulation.
- How it works: The consultant builds a digital twin of your building and compares its annual energy consumption against a “reference” building that perfectly matches the DtS rules.
- The Benefit: If your building uses less energy overall than the reference model, you pass—even if some specific parts (like a massive glass facade) don’t meet the standard DtS rules. This offers design flexibility.