The National Construction Code (NCC) is Australia’s primary set of technical standards for building design and construction. Updated every three years, it ensures buildings meet evolving safety, sustainability, and performance expectations. As NCC 2025 approaches its finalisation stage, the Australian Building Codes Board (ABCB) has released a public comment draft detailing the proposed amendments. This article highlights the key changes when compared to NCC 2022, including updates in energy efficiency, fire safety, condensation management, waterproofing, structural performance, and compliance pathways. By understanding these changes in depth, industry professionals can prepare effectively for upcoming enforcement deadlines and align with best practices.

1. Energy Efficiency and Sustainability Upgrades

Commercial Buildings

Energy efficiency is a major focus of NCC 2025, with several key changes aimed at reducing operational carbon footprints and improving building performance:

• Enhanced Thermal Performance: Stricter Deemed-to-Satisfy (DTS) provisions aim to improve Total System U-Values for wall-glazing constructions, reducing energy loss and improving insulation standards.
• Mandatory On-Site Renewable Energy: Buildings will require photovoltaic (PV) systems, decreasing reliance on fossil fuels and promoting sustainability through on-site energy generation.
• Support for Electrification: Increased provisions for all-electric buildings, ensuring a transition from gas-powered systems to a renewable-friendly infrastructure.
• HVAC System Efficiency Standards: New guidelines introduce improved energy ratings for heating, ventilation, and air conditioning (HVAC) systems, leading to lower energy consumption and better indoor air quality.

Residential Buildings

• EV Charging Infrastructure: Class 2, 3, 5, 6, 7b, 8, and 9 buildings must include dedicated electrical distribution boards (EDBs) and charging capacity for electric vehicles (EVs). This ensures readiness for increasing EV adoption across Australia.
• Expanded Solar Panel Requirements: Class 3-9 buildings must cover 100% of available roof space with solar panels where feasible, with limitations to avoid grid overloading and provide resilience to energy shortages.
• Building Fabric Improvements: Enhanced minimum insulation requirements in walls, roofs, and floors to reduce thermal bridging and improve building efficiency.

2. Condensation Management Enhancements

Condensation risks, particularly in colder climates, are addressed with:

• External Wall Construction Changes:
  • Climate zones 1-5: External walls must include vapour-permeable wall wrap to allow moisture control without compromising insulation.
  • Climate zones 6-8: Walls must feature drained and ventilated cavities (minimum 18mm), preventing mould growth and water accumulation.
• Roof Space Ventilation Adjustments: Requirements now extend to climate zones 4 & 5 (coastal NSW), in addition to zones 6-8, ensuring adequate airflow to mitigate condensation-related damages.
• Compliance with AS 4200.1: New standards for vapour control layers and membranes ensure long-term durability and effectiveness in moisture mitigation.

3. Structural Performance Updates

• New Minimum Reliability Levels: Structural components must meet higher performance benchmarks to ensure long-term durability and safety.
• Refined Structural Verification Methods: Standards now account for combined actions (e.g., wind, seismic, and live loads) instead of assessing each factor separately, leading to more robust engineering practices.
• Removal of Expert Judgement: Structural and fire safety solutions must be verified through approved engineering methods rather than subjective expertise, leading to higher levels of design certainty and reduced project risks.

4. Fire Safety Improvements

Car Park Fire Safety

• Increased Fire-Resistance Levels (FRL):
  • Open-deck car parks (Type A & B) and sprinkler-protected car parks (Type A under another building) no longer receive FRL concessions.
  • FRLs increase from 60/60/60 to 120/120/120 for key car park structures, providing enhanced fire containment measures.
• Sprinkler Protection Expansion:
  • Any car park with more than 40 spaces requires sprinklers, including open-deck designs.
  • Car stackers must now have dedicated sprinkler protection, reducing the risk of fire spread in densely packed vehicle storage areas.

Wayfinding and Exit Signage

• D3D31 – Wayfinding Signage (New Clause):
  • Required in all buildings to aid emergency coordination.
  • Stairs and floor levels must have unique identifiers (eg “Stair A,” “Level 3”), ensuring clear navigation during emergencies.
• Fire-Isolated Exit Re-Entry Regulations:
  • Strengthened fail-safe alarm requirements for re-entering from fire-isolated stairwells, ensuring safe egress and accessibility during fire incidents.
• Enhanced Emergency Lighting Standards: Updated exit and emergency lighting specifications ensure compliance with AS 2293, improving visibility during evacuation.

5. Waterproofing and Weatherproofing Enhancements

• Unified Water Management Standards: Surface water management now integrates external waterproofing and weatherproofing, standardising best practices across all building classifications.
• Class 7 & 8 Buildings No Longer Exempt: Previously excluded, these structures (e.g., warehouses, factories, substations) must now meet full waterproofing compliance, reducing long-term maintenance issues.
• Drainage Grading and Substrate Regulations: Grading must meet 1:80 slope (12.5mm per metre) for effective drainage, with new substrate material requirements ensuring long-term durability against water ingress.
• Expanded Requirements for Balcony Waterproofing: New standards mandate improved membrane and drainage solutions for balconies in multi-storey developments, reducing risks of water penetration into living spaces.

6. Compliance and Enforcement Timelines

Development Approval (DA) and Construction Certificate (CC)

• Before 1 May 2025: NCC 2022 applies if a DA is issued and the CC application is lodged before this date.
• After 1 May 2025: NCC 2025 applies to all new CC applications, ensuring alignment with the latest construction standards.
• Multi-Storey Buildings: If a CC application for the ‘entrance floor’ is lodged before 1 May 2025, NCC 2022 applies to the entire building, preventing fragmented compliance issues.

Crown and CDC Projects

• Crown Projects: Must comply with the NCC in force at the time of the tender invitation.
• Complying Development Certificates: Certifiers must confirm NCC compliance at the time of application, ensuring consistent enforcement across jurisdictions.

Conclusion

NCC 2025 introduces significant changes aimed at improving sustainability, fire safety, structural performance, and overall building resilience. The enforcement timeline requires industry professionals to proactively plan for compliance transitions. As regulations evolve, industry professionals must stay informed to ensure compliance and best practices in all future projects. By staying ahead of these changes, architects, builders, and developers can ensure projects are future-proofed, compliant, and aligned with Australia’s evolving construction landscape.

As a proactive building surveyor consultancy, we have been reaching out to clients to walk them through the proposals and how they may impact projects. Keep in mind that there may well be amendments prior to finalisation, we await the full picture, but at least we are raising awareness.