NCC Section J Changes: What Changed in 2019, 2022 and 2025?

NCC 2019 introduced a major commercial stringency increase. It strengthened façade, fabric, mechanical-services and lighting requirements and expanded the available Verification Methods.

NCC 2022 retained much of the commercial performance foundation established in 2019, but reorganised Section J and added stronger provisions for energy monitoring, electric vehicle infrastructure and future solar and battery systems.

NCC 2025 introduces another significant commercial uplift for relevant buildings, with mandatory on-site solar PV, higher requirements for building envelopes and services, and improved lighting-control requirements.

The latest published edition does not necessarily become legally applicable to every project on the same date. Each state and territory determines adoption, transition arrangements and local variations.

 

Section J is the energy-efficiency section of NCC Volume One. It establishes requirements that may affect multiple parts of a commercial building rather than one isolated design element.

Depending on the building and applicable edition, Section J may address:

• building fabric;
• walls, glazing and façade performance;
• roofs and floors;
• building sealing;
• air-conditioning and ventilation;
• artificial lighting and power;
• heated water systems;
• energy monitoring;
• electric vehicle infrastructure; and
• on-site distributed energy resources.

When the NCC changes, the effects can extend well beyond the Section J report itself.

A new edition may influence:

• glazing selections;
• façade ratios and shading;
• insulation build-ups;
• thermal-bridge calculations;
• roof planning;
• mechanical equipment;
• lighting controls;
• electrical switchboards;
• renewable-energy systems; and
• the selected compliance pathway.

For a broader explanation of the overall framework, visit the Section J Knowledge Hub.

 

NCC 2019 was a major turning point for commercial building energy efficiency. It substantially strengthened the provisions applying to relevant Class 2 common areas and Class 3 to 9 buildings.

A quantified Performance Requirement

The main commercial building energy-efficiency Performance Requirement was revised to include a quantified level of regulated energy consumption for conditioned buildings.

This gave the Performance Requirement a more measurable basis and connected the required level of efficiency with the function of the building, the energy consumed by regulated services and the level of occupant comfort expected from the building use.

A whole-façade approach

One of the most important practical changes was the move towards assessing walls and glazing as a combined wall-glazing construction.

Façade compliance became more clearly influenced by the interaction between:

• glazing U-values;
• solar heat gain coefficients;
• wall thermal performance;
• façade area;
• orientation;
• shading; and
• the proportion of glazing to opaque construction.

The change made façade design a more integrated Section J consideration rather than treating walls and glazing as entirely separate compliance exercises.

Greater recognition of thermal bridging

NCC 2019 made the effect of framing and thermal bridges harder to overlook when determining Total R-Values and overall envelope performance.

Metal framing and other conductive elements can bypass insulation and reduce the real thermal resistance of a wall, roof or façade assembly. A product-level insulation R-value does not necessarily represent the performance of the complete construction.

This had practical implications for:

• steel-framed walls;
• metal-framed roofs;
• insulation continuity;
• spandrel panels;
• structural penetrations; and
• construction details around conductive framing.

Project teams increasingly needed to consider the performance of the complete assembly rather than relying only on nominal material values.

Expanded Verification Methods

NCC 2019 expanded and revised the available Verification Methods. These changes included:

• a NABERS Energy pathway for eligible office buildings;
• a Green Star-based Verification Method;
• revisions to the reference-building method commonly known as JV3;
• thermal-comfort requirements within the modelling pathway; and
• a building-envelope sealing Verification Method using air-permeability testing.

JV3 was revised so that annual greenhouse-gas emissions became the principal comparison between the proposed building and the reference building.

This allowed the modelling pathway to consider the interaction between the building envelope, regulated services, different energy sources and eligible on-site renewable energy.

Stronger services and lighting requirements

The 2019 edition also strengthened multiple requirements for building services, including provisions relating to:

• air-conditioning controls;
• mechanical ventilation;
• fan and pump systems;
• pipework insulation;
• boilers and chillers;
• packaged air-conditioning equipment;
• artificial lighting;
• lifts and escalators; and
• energy monitoring.

NCC 2019 was therefore much more than a façade update. It represented a broader uplift across both passive building elements and active building systems.

 

NCC 2022 did not repeat the same scale of commercial stringency increase introduced in 2019. Its commercial Section J changes focused more strongly on restructuring, clarification, energy monitoring and readiness for future distributed-energy systems.

Section J was reorganised

The numbering and structure of Section J changed significantly. Under NCC 2022, the section is arranged into:

• Part J1 — Energy-efficiency Performance Requirements;
• Part J2 — Application of the energy-efficiency provisions;
• Part J3 — Elemental provisions for relevant Class 2 sole-occupancy units and Class 4 parts;
• Part J4 — Building fabric;
• Part J5 — Building sealing;
• Part J6 — Air-conditioning and ventilation;
• Part J7 — Artificial lighting and power;
• Part J8 — Heated water and pool or spa plant; and
• Part J9 — Energy monitoring and on-site distributed energy resources.

This changed many familiar clause references. A clause number used in an NCC 2019 report should not be assumed to represent the same location in NCC 2022.

For project teams, this means that older reports, specifications and drawing notes may require more than a simple change to the edition date.

JV3 became J1V3

The reference-building Verification Method commonly known as JV3 became J1V3 under the NCC 2022 numbering structure.

The method continued to compare the annual greenhouse-gas emissions of a proposed building with those of a reference building based on the applicable Deemed-to-Satisfy provisions.

It also retained safeguards intended to prevent weak envelope performance from being offset without limit by efficient building services.

The industry still commonly uses the name “JV3”, but assessment documentation should identify the formal Verification Method and NCC edition applying to the project. For a fuller explanation, visit the JV3 Knowledge Hub.

Electric vehicle infrastructure

Part J9 introduced provisions intended to make relevant carparks ready for the future installation of electric vehicle charging equipment.

These requirements do not necessarily mean that every required charging point must be fully installed at completion. They address matters such as dedicated electrical distribution boards, control capability and electrical capacity for future chargers.

The application depends on the building classification, the associated carpark and the number of spaces involved.

Solar and battery readiness

NCC 2022 also introduced requirements intended to make future solar PV and battery installation easier.

For relevant buildings, these provisions can affect:

• space within the main electrical switchboard;
• switchboard capacity for future solar PV;
• labelled spaces for solar and battery systems; and
• retention of suitable roof area for potential PV installation.

The key distinction is that NCC 2022 generally focused on facilitating future installation. It did not universally require every relevant commercial building to arrive with a complete solar PV system under this provision.

Expanded energy monitoring

Part J9 also addresses the monitoring of energy use within larger buildings. Depending on the building, separate time-of-use monitoring may be required for systems such as:

• air-conditioning plant;
• artificial lighting;
• appliance power;
• central heated water;
• lifts, escalators and moving walkways;
• on-site renewable energy;
• electric vehicle charging;
• battery systems; and
• other ancillary plant.

The monitored information may also need to be collated through a common interface so that building energy use can be stored, reviewed and analysed over time.

 

NCC 2025 returns the primary energy-efficiency focus to commercial buildings.

The national changes to Volume One Section J for buildings other than Class 2 introduce measures intended to reduce operational energy consumption.

The main published areas of change are:

• mandatory on-site solar photovoltaic systems;
• higher requirements for building envelopes and services; and
• improved lighting-control requirements.

Mandatory on-site solar PV

The move from solar readiness to installed solar PV is one of the clearest differences between NCC 2022 and NCC 2025.

Under NCC 2022, the relevant provisions primarily preserved electrical capacity and suitable roof space for a possible future installation.

Under NCC 2025, on-site solar PV becomes an installed compliance consideration for relevant buildings, subject to the applicable provisions, calculation method and available exemptions.

This may require earlier coordination of:

• available roof area;
• mechanical plant locations;
• roof lights;
• maintenance access;
• trafficable zones;
• overshadowing;
• electrical infrastructure;
• structural allowances; and
• the size and location of the proposed PV system.

Solar can therefore no longer be treated only as a future sustainability upgrade to be considered after the main roof design is complete.

Higher building-envelope requirements

NCC 2025 also increases the performance expected from relevant commercial building envelopes. The implications may extend to:

• roof and wall insulation;
• glazing systems;
• façade U-values;
• solar heat-gain control;
• building sealing;
• thermal bridging; and
• the relationship between glazing and opaque construction.

A design that achieved a Deemed-to-Satisfy outcome under an earlier edition should not automatically be assumed to achieve the same outcome under NCC 2025.

Façade review may need to begin earlier, particularly for highly glazed buildings, buildings with challenging orientations and projects using non-standard construction systems.

Higher building-services requirements

Commercial building services are another major area of uplift. Depending on the project, the revised requirements may influence:

• air-conditioning efficiency;
• ventilation systems;
• fans and pumps;
• system controls;
• heated water;
• equipment selections;
• system zoning; and
• the interaction between energy sources and operational emissions.

This makes alignment between the Section J assessment and mechanical, electrical and hydraulic documentation increasingly important.

Improved lighting controls

NCC 2025 strengthens commercial lighting-control requirements as well as considering installed lighting power.

Depending on the space and building type, this may affect:

• occupancy-based controls;
• time-based controls;
• lighting zones;
• daylight-responsive control;
• switching arrangements; and
• the control information shown on electrical drawings.

The compliance question is therefore not limited to how much lighting power is installed. The way the lighting is controlled and documented also matters.

 

Area	NCC 2019	NCC 2022	NCC 2025
Main direction	Major commercial stringency uplift	Restructuring, clarification and infrastructure readiness	Further commercial performance uplift
Façade	Whole wall-glazing approach introduced	Framework retained and reorganised	Higher envelope requirements
Thermal bridging	Greater recognition in complete-system calculations	Requirements retained within the reorganised framework	Remains important to higher envelope performance
JV3	Revised around greenhouse-gas comparison and thermal comfort	Renamed J1V3 under the new structure	Must follow the updated rules applying to the new reference building
Energy monitoring	Existing provisions strengthened	Moved into Part J9 and expanded	Continues within the wider operational-performance framework
Electric vehicles	No equivalent readiness framework at the same scale	Future EV-charging infrastructure introduced	Requirements must be checked against the applicable final provisions
Solar PV	Renewable energy recognised within performance pathways	Solar and battery readiness introduced	Installed on-site solar PV introduced for relevant buildings
Lighting	Lower power allowances and stronger efficiency requirements	Framework reorganised and refined	Improved lighting-control requirements
Services	Significant efficiency uplift	Clarification and targeted updates	Higher commercial services requirements

 

The year shown in the NCC title does not by itself determine which edition legally applies to a project.

The applicable edition may depend on:

• the state or territory;
• the date the relevant application is lodged;
• the type of approval being sought;
• transitional provisions;
• whether substantial design or construction work has commenced;
• jurisdictional variations; and
• directions from the certifier or building surveyor.

NCC 2025 does not automatically take legal effect for every Australian project on one nationally uniform date.

For example, as at 19 June 2026, NSW has announced that it will adopt NCC 2025 from 1 May 2027. Different dates or transitional arrangements may apply in other jurisdictions.

Project teams should confirm the applicable edition before commissioning, updating or relying on a Section J assessment.

 

An older report may provide useful background information, but it should not be treated as a current compliance assessment without review.

Potential problems may include:

• superseded clause references;
• outdated façade calculations;
• different insulation requirements;
• outdated services efficiencies;
• missing Part J9 provisions;
• outdated energy or emissions factors;
• missing solar or EV-readiness requirements;
• different modelling profiles; and
• an incorrect reference-building baseline.

Even where the architectural design appears similar, a change in NCC edition may alter the compliance result.

The safer approach is to use the earlier report as project history and review the current design against the NCC edition legally applicable to the new work.

 

No.

The NCC is developed nationally, but states and territories give it legal effect through their own legislation and administrative arrangements.

Adoption dates, transition periods and jurisdictional variations may differ.

A project should therefore not rely only on a general statement that NCC 2025 has been published or is available. The approval team should confirm whether the edition has been adopted for the project in the relevant jurisdiction.

 

No. The major NCC 2025 commercial energy-efficiency changes have been identified for buildings other than Class 2.

Class 2 apartment buildings may also be affected by separate residential energy requirements, common-area provisions, state variations and jurisdiction-specific systems.

Mixed-use developments require particular care because different parts of one building may be subject to different energy-efficiency provisions and assessment pathways.

 

“JV3” remains the common industry name for the reference-building modelling pathway.

Under NCC 2022, the formal clause reference became J1V3 as part of the wider NCC numbering restructure.

The assessment should identify the correct Verification Method and NCC edition rather than relying only on the informal name.

For a comparison of prescriptive and modelling pathways, read Section J DTS vs JV3: Which Compliance Pathway Suits Your Project?

 

The first priority is to establish the NCC edition that is likely to apply.

Once that has been confirmed, the project team should:

1. review the building classification and project scope;
2. identify relevant jurisdictional variations;
3. confirm whether a DTS or Performance Solution pathway is likely to be used;
4. review the façade, glazing and construction systems;
5. coordinate roof space and solar requirements;
6. check mechanical, electrical and hydraulic assumptions;
7. document lighting and control strategies;
8. align the assessment with the current drawings and schedules; and
9. confirm the final compliance approach with the certifier or building surveyor.

For projects approaching a jurisdictional adoption or transition date, an early review against both the currently applicable and incoming editions may help identify future design risk.

The information commonly required to begin a review is explained in What Documents Are Needed for a Section J Report?

 

Across NCC 2019, NCC 2022 and NCC 2025, Section J has moved progressively towards a more coordinated commercial building-performance framework.

NCC 2019 substantially strengthened commercial building fabric and services.

NCC 2022 reorganised the framework and added energy monitoring, distributed-energy readiness and future EV infrastructure.

NCC 2025 brings renewable-energy installation and stronger envelope, services and lighting-control requirements further into the minimum commercial building standard.

The practical result is that Section J increasingly needs to be considered during design development rather than treated only as a final report prepared shortly before approval.

Section J Knowledge Hub

Understand the overall commercial energy-efficiency framework, what it covers and how assessments are approached.

Section J DTS vs JV3

Compare the prescriptive and modelling pathways and when each approach may suit a commercial project.

Documents Needed for Section J

Review the drawings, schedules, construction details and services information commonly needed to begin an assessment.