NCC 2025 Volume One — What's Changed
National Construction Code 2025 Preview Draft vs NCC 2022 Deep Research Report by Claude — March 2026
Overview
The NCC 2025 Volume One (Building Code of Australia — Class 2 to 9 buildings) introduces significant new provisions and updates across fire safety, water management, energy efficiency, accessibility, sanitary facilities, and electric vehicle infrastructure. The preview draft was released in February 2026, with earliest adoption expected from May 2026 (jurisdiction-dependent).
This report covers three areas:
- What's NEW — provisions that did not exist in NCC 2022
- What's UPDATED — existing provisions that have been revised
- Why — the drivers and rationale behind the changes
1. What's NEW in NCC 2025
1.1 EV Charging Infrastructure (Section L — New)
NCC 2025 introduces mandatory electric vehicle charging provisions for the first time, requiring new buildings to be "EV-ready" with electrical infrastructure capacity.
Requirements by building class:
| Building Class | Description | EV-Ready Requirement |
|---|---|---|
| Class 2 | Apartments | Minimum % of car spaces with conduit + switchboard capacity |
| Class 3 | Hotels, motels, hostels | Charging infrastructure for guest parking |
| Class 5 | Offices | Conduit pathways and electrical capacity for future chargers |
| Class 6 | Retail/shops | Infrastructure provisions for customer and staff parking |
| Class 7 | Carparks/warehouses | Scalable electrical backbone for staged charger rollout |
| Class 8 | Laboratories/factories | Provisions proportional to expected vehicle demand |
| Class 9 | Public buildings (healthcare, assembly, aged care) | Charging provisions for staff and visitor parking |
Key design elements:
- Conduit pathways from switchboard to car spaces
- Electrical switchboard capacity reservations
- Metering provisions for individual billing
- Load management system compatibility
1.2 Water Management Framework (Part F1 — Restructured/New)
NCC 2025 consolidates and expands water management into a unified framework under Part F1. This replaces the fragmented approach in NCC 2022 where waterproofing, weatherproofing, and water shedding were treated somewhat separately.
New framework structure:
Notable new/strengthened requirements:
- Minimum 1:80 gradient for water shedding on balconies, podiums, and accessible areas
- 70mm step-downs at door thresholds to external tiled areas
- Expanded scope to cover previously unregulated junctions and interfaces
- Performance-based pathways with clearer verification methods
1.3 All-Gender Sanitary Facilities (Part F4 — New Provision)
NCC 2025 formally introduces provisions for all-gender (unisex) sanitary facilities in certain building types, reflecting contemporary approaches to inclusive design.
- Applicable to new Class 5, 6, and 9 buildings above certain thresholds
- Provisions allow all-gender facilities to count toward overall sanitary fixture requirements
- Privacy and safety design requirements included (full-height partitions, individual lockable compartments)
2. What's UPDATED in NCC 2025
2.1 Fire Safety — Carpark Sprinklers (Section C)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Sprinkler trigger | Generally 40+ vehicles in enclosed carparks, but inconsistent | Clarified: sprinklers required for carparks with 40+ car spaces in Class 2-9 buildings |
| Open-deck carparks | Typically exempt | Now included where fire risk assessment warrants |
| EV fire risk | Not addressed | Acknowledged — EV battery fires specifically referenced in guidance |
Rationale: EV battery fires burn longer and more intensely than conventional vehicle fires. Updated sprinkler requirements ensure water suppression infrastructure matches the evolving vehicle fleet.
2.2 Waterproofing & Water Shedding (Part F1)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Balcony gradients | General guidance, no minimum specified | 1:80 minimum gradient mandated |
| Door step-downs | Varied/unclear | 70mm step-down at doors to external tiled areas |
| Scope | Primarily internal wet areas | Extended to balconies, podiums, terraces, and external junctions |
| Verification methods | Limited | Expanded performance-based verification pathways |
2.3 Condensation Management (Part F8)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Vapour permeance | General requirements | Class 4 vapour permeance classification for barriers |
| Climate zones | Limited zone coverage | Extended to Climate Zones 4 and 5 |
| Ventilation | Basic requirements | Enhanced mechanical and passive ventilation requirements for moisture-prone areas |
| Roof spaces | General guidance | Specific condensation control measures for roof and ceiling spaces |
2.4 Women's Toilet Ratios (Part F4)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| General ratio (F:M) | 1:1.25 | Maintained at 1:1.25 for most building types |
| Theatres & cinemas | 1:1.25 | Increased to 1:1.8 (F:M) |
| Assembly buildings | 1:1.25 | Increased ratios for high-attendance venues |
Rationale: Evidence-based adjustment to reduce queue times at high-turnover venues. Research demonstrated that equal fixture counts result in significantly longer wait times for women due to physiological and practical differences in facility use time.
2.5 Energy Efficiency (Section J)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Commercial stringency | 2019 baseline | Increased stringency — tighter thermal performance targets |
| Glazing | Prescriptive SHGC/U-value limits | Updated values reflecting current glazing technology |
| HVAC | Efficiency baselines | Raised minimum efficiency for commercial HVAC systems |
| Renewables | Optional pathway | Strengthened integration of on-site renewable provisions |
| Reporting | JV3 verification method | Enhanced NatHERS and JV3 alignment |
Rationale: Aligned with Australia's trajectory toward net zero emissions by 2050 and the National Energy Performance Strategy.
2.6 Structural Provisions (Section B)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Performance-based assessment | General framework | Enhanced documentation and verification requirements |
| Referenced standards | AS/NZS 1170 suite (2021 versions) | Updated references to latest published editions |
| Robustness | Implicit requirements | More explicit progressive collapse and structural robustness provisions |
2.7 Accessibility (Part D — AS 1428.1 Update)
| Aspect | NCC 2022 | NCC 2025 |
|---|---|---|
| Referenced standard | AS 1428.1-2009 | Updated to AS 1428.1:2021 |
| Luminance contrast | General requirements | Strengthened minimum luminance contrast ratios |
| Tactile indicators | Basic provisions | Updated installation and spacing requirements |
| Accessible toilets | AS 1428.1-2009 layout | Revised layout requirements per 2021 standard |
3. Reasons Behind the Changes
3.1 Summary of Drivers
3.2 Detailed Rationale
Building Defect Prevention
Water ingress and waterproofing failure remain the number one category of building defects in Australia. The consolidated water management framework directly targets this by:
- Mandating measurable gradients (1:80) instead of vague "adequate" requirements
- Specifying step-down dimensions (70mm) to prevent threshold water entry
- Expanding scope to cover balconies and terraces — a known defect hotspot
Condensation and mould issues have increased as buildings become more airtight for energy efficiency. The extended Climate Zone 4-5 coverage and Class 4 vapour permeance requirements address the unintended consequences of improved building sealing.
Safety Modernisation
The original carpark sprinkler provisions were developed when vehicle fleets were entirely internal-combustion. EV battery fires present different characteristics (longer duration, thermal runaway, toxic fumes), requiring updated fire suppression infrastructure. The 40+ car space threshold has been clarified and open-deck exemptions narrowed.
Structural robustness provisions address lessons learned from international building failures and reflect updated understanding of progressive collapse risks.
Environmental & Climate Policy
Australia's commitment to net zero emissions by 2050 requires the building sector (responsible for approximately 25% of national energy consumption) to significantly improve performance. NCC 2025's energy efficiency updates and EV charging infrastructure requirements directly support:
- The National Energy Performance Strategy
- State and territory electric vehicle strategies
- COAG Energy Council commitments
Social Equity & Inclusivity
Updated women's toilet ratios for theatres and cinemas are evidence-based, addressing well-documented queue time disparities. The introduction of all-gender sanitary facilities reflects contemporary understanding of inclusive design. Updated accessibility standards (AS 1428.1:2021) incorporate over a decade of research and user feedback since the 2009 edition.
4. Implementation Timeline
Note: Each state and territory determines its own adoption date and transition arrangements. Some jurisdictions may adopt NCC 2025 provisions progressively.
Sources
- Australian Building Codes Board (ABCB) — NCC 2025 Preview Draft, Volume One
- NCC 2022 Volume One (Building Code of Australia)
- ABCB public consultation documentation
- Housing Industry Association (HIA) — NCC 2025 analysis
- MBC Group — NCC 2025 technical commentary
- Engineers Australia — structural provisions review
- Department of Climate Change, Energy, the Environment and Water (DCCEEW)
- Australian Treasury — building reform documentation
Report generated March 2026. Based on the NCC 2025 Preview Draft — final adopted version may differ.