The speaker is Michael Ho.
Hello and welcome to today’s practitioner education series. We’ll be going through the key changes in NCC 2025 Volume One — the Building Code of Australia.
The purpose of this presentation is to ease the transition to the new Volume 1 of NCC 2025 and to equip practitioners to confidently apply these changes to their commercial projects.
The Learning Objectives are to:
- Identify key changes to be brought by NCC 2025 against the NCC 2022 Amendment 2
- To interpret the changes, and
- To understand some of the practical implications of these changes
As you can see on screen, we have the familiar 2022 Amendment 2 cover on the left which we’ve been working with since May 2023 and on the other side , NCC Volume 1 2025 released by the ABCB on 1 February 2026.
We are currently at the Preview phase of the NCC 2025 that was released on the 1st of February 2026 for public information.
From the 1st of May 2026, the NCC 2025 will be adopted by Victoria. We note that the Victorian Variations are yet to be published and we will provide a separate announcement and presentation once they are finalised.
The Australian Building Codes Board has focused this edition on practical improvements which includes enhanced structural reliability, stronger fire safety in testing materials and carparks, improved accessibility with wayfinding, better water management in buildings and commercial energy efficiency gains.
In addition, the Victorian Variations to the NCC have yet to be confirmed and we’ll provide a separate announcement on the changes when released.
Today, we'll go section by section through the major updates, starting with Structure (B), Fire Resistance (C), Access and Egress (D), Services and Equipment (E), Health and Amenity (F) and Energy Efficiency (J).
My goal is to highlight the highest-impact changes and some practical takeaways in relation to building projects.
Starting with Section B Structure.
There are two changes here that represent a significant step up in how structural safety is demonstrated, especially for Performance Solutions.
The one that will affect structural engineers the most is the major update to demonstrating structural reliability.
In NCC 2022 Amendment 2, to demonstrate structural reliability against performance requirement B1P1, the performance solutions allowed qualitative methods.
In 2025 that has changed.
B1P1 has been amended and the requirement is now more specific, where each structural component must withstand all relevant actions and at minimum, meet the reliability indices which are listed in the new Tables B1P1a, B1P1b, and B1P1c. Note that A2G2(5) requires the performance solution against B1P1(2) to demonstrate equivalence to the DtS provisions.
These minimum reliability indices values vary by Importance Level (1 to 4) and by action type. The reliability index is essentially a “safety score” — the higher number means a lower chance of failure in any given year. This change reduces subjectivity in Performance Solutions.
The old B1P2 (structural resistance) has been deleted and folded into the new B1P1 wording — the rest of Part B1 has been renumbered accordingly.
In addition, B1V1 now requires to account for combinations of actions (like wind or earthquake), not just individual loads. This includes component variability factors and run probabilistic calculations to confirm the minimum annual reliability indices meets or exceed the tables mentioned previously.
Engineers now need to quantify their performance solutions and deem equivalence to the deemed to satisfy provisions. This is a deliberate move away from subjectivity.
There is a transitional Note in B1P1 and B1V1 — you can use the 2022 Amendment 2 approach, for 12 months after adoption of the NCC 2025.
These changes make structural Performance Solutions more objective, consistent, and quantifiable.
Next up — a very practical change that ties structure directly to waterproofing.
B1D2(b) has been amended to require design actions allow for a 10-year deflection of structural substrates. Designs that incorporate concrete slabs, podiums, balconies, and roofs, are required to factor in 10-year deflection.
This is in line with the surface falls required by the new Part F1 (water management) and will be maintained over time.
Long-term creep or settlement can cause ponding and water ingress defects years later, This requirement requires consideration by the structural engineer to prevent that.
There are also updates to the wind loading standard (being AS1170.2 – 2021 edition including Amendments 1 and 2) in B1D3 and Specification 4
In Victoria and Melbourne, which mostly falls in Region A, the impact is marginal. Wind speeds and design pressures stay very similar to what is already being used, so no major redesigns needed for most buildings in Melbourne.
Coastal or edge sites should double-check the updated wind region maps, there are a few spots near borders or bays have minor impacts to cladding or fixings, but it’s business as usual for most Victorian projects.
Two more items to close out Section B.
Metal roofing and cladding in cyclonic zones now explicitly requires compliance with AS 1562.1 — that’s the new subclause B1D4(k).
This means more rigorous fixings, installation details, and testing, a tighter standard for higher-wind zones. It’s mainly relevant outside Victoria, but it aligns with the updated wind loading in AS/NZS 1170.2 and ensures roofing performs reliably in extreme conditions.
In addition, the reference to ‘small sized, low speed automatic lifts’ in B1D4(m)(i)(c) has been removed to reflect removal in Section E.
Moving on to Section C – Fire Resistance — the changes that will affect materials and verification.
There are two big practical shifts here, plus a few smaller clarifications.
First, testing reliability is now stricter.
C1V3 (external wall classification via AS 5113) and S7C4 (fire hazard properties — things like Group Number, Critical Radiant Flux, Spread-of-Flame Index, and Smoke-Developed Index) must now be done by an Accredited Testing Laboratory, which is defined to be an organization accredited or recognized by the National Association of Testing Authorities Australia (NATA).
This means that all test reports for external walls classification testing and fire hazard properties will need to be verified against NATA accreditation.
In 2022 Amendment 2, this was common practice for test reports to be undertaken by NATA but not mandatory — the Code didn’t force it.
In 2025, it does. There is a transitional note in both clauses aligned with the adoption date.
Moving onto changes to fire ratings, there are two small but useful updates in Section C.
First — Specification 5 Clause 9 has been amended to clarify when Class 7 parts (such as ancillary uses to the residential components being storage, carparks and the like) can be treated as Class 2 or 3 for fire-resistance level purposes.
This clarification improves the application in mixed Class 7/2/3 buildings. The wording is now clearer and reduces ambiguity of when Class 7 components could be treated as a Class 2 or 3 building. For example, a carpark in a Class 2 building with a rise in stories of 3 can have same FRLs requires for Class 2 components.
Second — a new provision, S5C11, allows fire-protected steel in Type A construction in certain circumstances.
This means a loadbearing internal wall or loadbearing fire wall may be constructed of fire protected steel in a Class 2 or 3 building or the uppermost storey of any other classifications.
There are conditions associated with this use including effective height less than 25m, and a sprinkler system throughout the building.
This gives a level of flexibility for steel-framed construction in lieu of requiring concrete or masonry.
For example the fire rated walls on the top storey of a building, lets say class 2 would generally be load-bearing where supporting a roof, and would previously (under 2022) require to be concrete or masonry construction. This would typically be a fire engineered performance solution to have lightweight (or steel) construction.
Now the NCC has permitted lightweight construction (subject to the limitations).
The second major change is the significant tightening of carpark fire safety concessions.
Open-deck carparks that form part of multi-classified buildings — think residential apartments above retail, or mixed-use podium carparks — no longer receive the previous concessions on reduced fire-resistance (e.g. 60 min FRLs) levels unless they are adequately sprinkler-protected. This mainly hits Specification 5 (S5C19 and S5C22).
In addition, sprinkler exemptions are now removed in open-deck carparks in Mult classified buildings where car stackers are installed, or more than 40 vehicles are present.
These changes recognise the increased fire load from larger modern vehicles, electric vehicles with batteries, and mechanical stackers.
There’s also a small clarification on Class 2 and 3 buildings which have the timber concession – this applies to the lowest storey and has clarified loadbearing elements only be constructed of concrete or masonry. This was previously broad and didn’t specify loadbearing elements).
For example, a Class 2/3 building with the timber concession, will only require a load-bearing column to be concrete/masonry, where as a light-weight partition walls in the same storey won’t require to be.
Moving on, let’s look at a few important clarifications in Section C around pressurization equipment, openings in external walls and smoke-proof walls – mostly small wording changes, but they make compliance clearer and more consistent.
First – pressurisation equipment (C3D13(2)(b)).
The wording now makes it clear that the equipment must serve the entire exit in accordance with AS 1668.1. In 2022 Amendment 2 it said “stairs” – which led to some confusion. Now it explicitly covers all parts of the exit, not just the stair shaft. This aligns much more closely with AS 1668.1 and ensures proper smoke control across the full exit path.
Second – extent of protection to openings (C4D3(1) and related clauses).
Previously it was ambiguous: if any part of an external wall had an FRL, there was some interpretations that assumed the whole wall needed protection. The clarification is now very clear: protection is only required on the parts of the external wall that actually have an FRL. Non-fire-rated portions are exempt. In the example we can see two separate buildings as fire source features to one another and only the openings within the indicated fire rated external walls need to be protected where exposed to each other.
It is noted the definition of fire source feature has been updated to include the construction edge or perimeter of another building on the allotment which is not a Class 10 building and which has a use that constitutes a fire load.
Third – smoke-proof walls and duct penetrations (S11C2 and S11C3).
The specifications for smoke-proof walls have been clarified. There is now an explicit mention that smoke dampers are required in duct penetrations through these walls, in accordance with AS 1682.1.
Finally – doors in zone-pressurised fire and smoke compartments (S11C4).
The previous concession has been removed. Doors serving zone-pressurised fire compartments now must form a full height smoke reservoir. There is no longer an exemption for the 400 mm smoke reservoir above smoke doors.
This applies to all doors in smoke-rated walls in these zones, even in zone pressurized compartments. This would primarily impact health-care buildings.
Let’s move to Section D – Access and Egress
There are some clarifications around minor ramps.
D1P2 has now excluded threshold ramps from requiring features like slip resistance and handrails — so these features no longer apply to minor ramps.
Note slip resistance would still apply to threshold ramps provided for people with a disability.
Meanwhile, there are also some noticeable updates regarding wayfinding signage requirements.
D1P10 introduces a new Performance Requirement for wayfinding signage — clear directional and identification signs to assist in fire brigade intervention and facilitate occupant egress.
D3D31 is the Deemed-to-Satisfy follow-up — it makes signage mandatory for stairways, floor levels, and sole-occupancy units, including tactile, Braille, and high-contrast visual elements.
Next in Section D – Access and Egress — a few practical clarifications and extensions that improve safety and simplicity.
First — D2D8 (width of exits) now considers the required width of exits forming part of fire compartments served by horizontal exits. Previously this was limited to the storey, mezzanine, or open spectator stand. Now it further defines the minimum exit size where fire compartments and horizontal exits exist — not just the storey. This ensures safer, more consistent egress in large floorplate buildings.
Second — re-entry from fire-isolated stairs (D3D27) has been extended across all Class 9 buildings and extended to Class 2, 3, 6, and 7a buildings. This was previously only applicable to some Class 9 buildings and buildings over 25 m effective height.
There are also additional signage requirements for every second storey where re-entry is not available.
These updates minimize the risk of being trapped in fire-isolated exits in public and residential buildings.
Third — threshold ramp details have been simplified. D3D16 removes old specific references to Class 9a and 9c buildings, making threshold requirements more uniform across classes. Compliance can now be achieved via threshold or step ramps (for accessible areas) or otherwise 190 mm. This reduces confusion in health and residential care projects and makes compliance more straightforward. Note that plant room and machinery rooms are exempt from this requirement.
Let’s move to Section E – Services and Equipment.
The changes here are practical and primarily focus on improving fire safety in carparks, clarifying ventilation and smoke damper provisions.
The most significant updates relate to carpark fire safety, building on what was introduced in Section C. Open-deck carparks in multi‑classified buildings must now be sprinkler‑protected to access FRL concessions, and additional sprinkler requirements apply where car stackers or more than 40 vehicles are present. As a result, sprinklers will be required in many more mixed‑use and open‑deck carparks. This directly addresses increased fire risks associated with larger modern vehicles, electric vehicles, and mechanical car stackers.
A further clarification applies to combined sprinkler and hydrant systems, where these systems are installed, all above‑ground pipes and fittings must be non‑plastic. Additionally, E1D2 now clarifies that AS 2118.6 is an acceptable standard for combined sprinkler–hydrant systems as well as FPAA101H (where applicable).
Moreover, fire hose reels are now exempt in small (<100 m2) fire‑separated areas where portable extinguishers are provided.
The next group of updates focuses on ventilation and smoke damper clarifications. Several clauses have had terminology updated to “ventilation systems,” aligning with AS 1668.1. And as mentioned previously, smoke dampers must now be specified in accordance with AS 1682.1.
E2D20(2) has also been refined to clarify that floor‑area thresholds for Smoke Hazard Management Systems apply specifically to the Class 9b portion of a building only (being more than 2000 m2), reducing previous misinterpretation.
Overall, these updates are largely wording and alignment improvements. They reduce ambiguity, improve consistency when applying AS 1668.1, and require minimal redesign for most projects.
Next, there are several updates relating to lifts and exit signage. Small sized, low‑speed automatic lifts are no longer permitted, and the corresponding clause E3D7(1)(e) has been deleted. This is as a result of those types of lifts attracting safety concerns.
E3D11 has also been clarified so that only a single fire service recall switch may control a group of lifts, preventing multiple conflicting switches.
In addition, new requirements in E3D11 and E3D12 require on‑site storage of fire service lift keys, typically located near the Fire Indicator Panel or within the Fire Control Centre. These changes remove outdated lift types and improve reliability and access for emergency services, with only minor coordination required for key storage.
A further update relates to photoluminescent exit signs. Hybrid photoluminescent exit signs are now permitted and referenced through SA TS 5367. These signs incorporate an internal light source to charge the photoluminescent material, offering a modern option with improved visibility during power failures. Specification 25 has also been updated to include the term “passive.”
There are also several smaller refinements.
Clarifications to emergency lift distribution confirm that while the number of emergency lifts does not increase, their location must be distributed across different lift shafts. For example, in a storey served by two or more shafts, emergency lifts cannot be grouped in the same shaft, ensuring redundancy during an emergency.
Finally, contrast requirements have been added for lettering on lift warning signs, improving legibility and safety.
In NCC 2025, Section F has been significantly restructured compared with NCC 2022 Amendment 2, with clearer intent and new defined term of “Water”.
The title of Part F1 has been re-named as the result of Section F re-structuring.
The Objectives of Section F, F1O1, has been clarified and broadened with a new terminology “Water” being introduced.
The Functional Statements have also been revised to reflect the outcomes of the Section F re-structuring.
The Section F now explicitly seeks to address all water impacts on buildings, including improved sub-surface water management that previous NCC was lacking.
In NCC 2025 Volume 1, the previous Part F3 (Roof and Wall Cladding) has been fully merged into Part F1, creating a more integrated approach to waterproofing, water shedding, and condensation mitigation.
All previous Performance Requirements have been consolidated into a single clause: F1P1 (Managing rainwater impact on the building and adjoining properties). This aligns with the intent of achieving comprehensive water management across the building and adjoining properties.
The Performance Requirement now utilises the new defined term “Water”, which broadens the scope beyond surface water to include potential damage from ground moisture, rising damp, groundwater, and other sources.
Notes to F1P1 clarify specific concerns for water management during rare heavy rain events on high-risk building elements susceptible to ingress. The notes also provide concessions for certain low-risk awnings and roofs.
In NCC 2022 Amendment 2, limitations and exemptions applied to weatherproofing and rising damp requirements for certain Class 7 and Class 8 buildings. NCC 2025 removes most of these exemptions. The change clarifies that only defined private garages are permitted to utilise limited exemptions from certain performance requirements.
The Verification Method from NCC 2022 Amendment 2 F3V1 is now NCC 2025 F1V1.
The updated provisions support a more robust and proactive approach to water management, ensuring that planning, design, and construction decisions consider long‑term performance. These changes aim to reduce water ingress issues, improve building resilience, and lower lifecycle maintenance and rectification costs.
F1D2 has been amended as part of the restructuring of Section F, integrating water management with wall and roof cladding provisions.
The clause now clearly identifies where certain DTS provisions in Part F1 do not apply and explicitly confirms that Part F1 covers all building elements exposed to rainwater, surface water, or ground moisture.
In previous editions, this scope had to be inferred. F1D2 is also referenced by B1D2(b), which requires structural substrates to account for 10‑year deflection to maintain falls.
The revised clause strengthens the link between structure and waterproofing, improving long‑term performance by ensuring falls and drainage are maintained over time.
F1D4 and F1D5 are new clauses that set out explicit requirements for falls, drainage and substrate materials for concrete roofs, balconies, podiums and similar horizontal surfaces.
For example, for a balcony, it now requires a 1:80 minimum gradient to a floor waste at the substrate.
In addition, F1D7 requires the membrane to be applied directly onto the substrate.
An option of finish being self-draining surface (e.g. pod pavers) or directly fixed to the membrane is required (per F1D10).
Further to the above, there is a minimum set-down of external areas from the internal floor to be minimum 70 mm. Both are measured from the structural substrate. Consideration to AS4654.2 minimum termination heights still apply as this relates to finished floor levels.
F1D12, F1D13 and F1D14 were previously located in NCC 2022 Amendment 2 Part F3 and have now been relocated into Part F1 as part of the broader restructuring that integrates all water‑management provisions.
These changes are largely administrative, with only minor wording updates for clarity.
F1D15 has been Amended to remove concession for certain Class 7 and 8 buildings and replace ‘garage’ with the defined term ‘private garage’.
The relocation and clarification of these clauses provide clearer guidance for roof and wall systems, particularly around water‑resistance expectations.
Finally, NCC 2025 Part F1 now fully incorporates what was previously NCC 2022 Amendment 2 Part F3, consolidating all relevant water‑management provisions into a single, more coherent section.
Moving to Part F4, F4D4(6) now requires sanitary product dispensers to be provided in facilities for use by females.
F4D4(12), (13) and (14) introduce new provisions that allow all‑gender sanitary facilities to be provided in place of separate male and female facilities in Class 3–9 buildings.
Up to 50% of required facilities may be all‑gender, provided hygiene, privacy, location and identification requirements are met.
Note ambulant toilet facilities are still required to be separate male and female under DtS and would still require a performance solution for all-gendered ambulant facilities where proposed.
Sanitary product dispensers and disposal units must be included where applicable.
Table F4D4i (for Class 9b buildings such as theatres and cinemas) now increases the required number of closet pans for female patrons, including an additional population bracket.
These projects will need to allow for increased female sanitary provision when planning space and fixture layouts.
F4D8(1)(a) has been amended to apply privacy requirements to all‑gender facilities. Full privacy — such as floor‑to‑ceiling partitions and lockable doors — is expected. This aligns with the new all‑gender options under F4D4.
In addition, F6D6 has been updated so that natural ventilation via openings (F6D7/F6D8) or mechanical systems, natural ventilation may now also be demonstrated using AS 1668.4. The clause also clarifies that ventilation requirements apply to any occupied room or space, reducing previous ambiguity (previously clause had only referenced room).
F6D12 (kitchen local exhaust ventilation) has been revised with minor wording changes. It now applies to all kitchens and refers to “a kitchen exhaust hood system,” aligning terminology more closely with AS 1668.1 for mechanical exhaust systems.
This is a small clarification that improves consistency in documentation and specification for kitchen exhaust installations.
In NCC 2022 Amendment 2, Part F8 addressed condensation risks but left some practical gaps, particularly around moisture in walls and roofs. NCC 2025 strengthens these provisions, providing clearer and more comprehensive Deemed‑to‑Satisfy requirements to reduce mould growth and moisture‑related deterioration.
F8D3 now requires all external wall systems to incorporate a drained and vented cavity, and any control layer between the primary insulation and cladding must achieve at least Class 4 vapour permeance in accordance with AS 4200.1. Direct‑fixed wall systems are no longer permitted in Climate Zones 6,7,8 which applies to most of Victoria due to elevated condensation risk. The Explanatory Information provides further guidance on acceptable construction methods. Note this doesn’t apply to single skin masonry and concrete walls or insulated sandwich panels (refer to subclause 5 for further information).
F8D5 and F8D6 set out distinct requirements for roof space ventilation, depending on whether the ceiling is parallel to the roof plane. These provisions aim to improve airflow, manage moisture, and reduce the likelihood of trapped condensation. Additional examples and clarifications are provided in the NCC 2025 Explanatory Information.
Moving onto Part G, G1D2(1) has been amended so that where a boundary fence also forms part of a swimming‑pool safety barrier, it must comply with the Non‑Climbable Zone (NCZ) requirements of AS 1926.1. This ensures consistent safety performance when boundary fences operate as part of the pool barrier.
G1D5 is a new clause requiring pumped swimming‑pool discharge to comply with AS/NZS 3500.2 and be directed into the sanitary drainage system, preventing discharge to stormwater or the ground. This reduces contamination risks and supports better environmental outcomes. Note this inclusion mirrors existing DTS in Vol 3 - C2D3 (Vol 3 C2P2 has same wording as G1P1). Reduces need for performance solution as there is now DTS for G1P1. Similar amendment provided for Vol 2.
S31C7 has been updated to clarify that the mechanical air-handling systems in buildings with atrium are required to comply with AS 1668.1 and installed as a hot layer smoke control system as defined in the Standards, unless varied by other clauses within Specification 31.
The change aligns NCC wording with AS1668.1 wording to avoid ambiguity.
Let's move to Section J – Energy Efficiency –
Overall, Section J in 2025 strengthens energy efficiency for commercial buildings (excluding Class 2s). It focuses on reducing energy consumption and greenhouse gas emissions through tighter building envelopes, more efficient services, and mandatory on‑site solar PV. A new note clarifies that Class 2 buildings continue to follow NCC 2022 Amendment 2, so all Class‑2 references have been removed from Section J.
Let’s start with Part J1, the updated Performance Requirements and Verification Methods.
J1P1 now sets more stringent, quantitative energy‑use and emissions targets and incorporates onsite renewable‑energy expectations.
J1P4 clarifies that “storage” means energy‑storage equipment and provides a concession where maximum practicable renewable generation and storage are already installed.
For Verification Methods,
J1V1 (NABERS) allows room‑temperature modelling for existing‑building modifications.
J1V2 (Green Star) now accepts only the “Green Star Buildings” rating.
J1V3 (Reference Building) tightens energy benchmarks, removes renewable offsets, and uses new calculation rules in Specification 48.
J1V4 (Envelope Sealing) aligns with new sealing and envelope‑tightness requirements.
The Application of Section J, clause J2D2, is also updated to align with changes in Part J4 and new requirements regarding onsite renewable energy systems.
The DTS pathways for building fabric, glazing, HVAC, lighting, power, and hot water are all substantially strengthened.
Examples include
- Glazing: Lower SHGC limits — requiring better glass or shading.
- HVAC: Higher minimum efficiency for chillers, fans, and plant.
- Lighting: Lower allowable lighting‑power densities → LED and smart‑control systems.
More specifically,
- J3 – Elemental Provisions for Class 4 Part of a Building: Updated thermal‑break rules, deletion of thermal‑bridging clause J3D6, revised waffle‑pod slab insulation, and expanded energy‑calculation requirements.
- J4 – Building Fabric (including Glazing): Clearer insulation‑installation rules, updated Total R‑values, PV/green‑roof concessions, and new SHGC/U‑value limits.
- J5 – Building Sealing: Wider application of sealing requirements, removal of Victorian concessions for roof lights/non‑conditioned spaces, mandatory seals on external doors, and expanded exhaust‑fan sealing.
- J6 – HVAC/Ventilation: Lower fan‑power limits, more modulating‑control scenarios, removal of low‑pressure/low‑volume concessions, and deletion of MEPS‑certified‑system concessions.
Finally let’s touch on the specifications in Section J.
- Specs 33 (NABERS) and 34 (Green Star): Updated rating methodologies, Green House Gas factors, and performance requirements.
- Spec 40 (Reference Building): Updated GHG calculations, inclusion of EV charging, and modernised lighting‑control requirements.
- New Specs 46, 47, 48: Define mandatory methods for calculating fan‑power ratio, chiller part‑load efficiency, and reference‑building zone‑load comparisons.
NCC 2025 Section J delivers a substantial uplift in commercial‑building performance: tighter envelope and services standards, mandatory solar PV, stronger verification pathways, and electrification readiness. Achieving compliance will require earlier and more detailed energy modelling, but the outcome is buildings that are more efficient, resilient, and aligned with a net‑zero future.
To close today’s presentation — NCC 2025 brings a focused, practical uplift across the Code. These updates strengthen structural reliability, improve fire‑safety pathways, clarify access and egress, update services and lift requirements, and deliver a major overhaul of waterproofing and condensation management. Section J then pushes commercial buildings toward a net‑zero‑ready future, with tighter DTS provisions, clearer verification methods, and mandatory onsite solar PV.
Thank you for your time. If you have any questions, please give us a call or email us at technicalenquiry@bpc.vic.gov.au.