National Construction Code Guide for Property Developers

The National Construction Code (NCC) is the minimum technical standard every building in Australia has to be designed and built to, expressed by building class, and the edition that binds your project is decided by your state or territory, not by the Australian Building Codes Board. That distinction is where most of the money sits. The 2025 edition became available for jurisdictions to adopt from 1 May 2026, but as at the date of writing it applied in some jurisdictions, was deferred in others, and had been switched off entirely in one. A cost plan priced against the wrong edition tends to be wrong by the amount of the new work, not by a rounding error.

The people holding the relevant inputs are your building surveyor or principal certifier, who decides which edition your approval is assessed under, and your quantity surveyor, who prices the difference. The energy and sustainability consultant usually owns the solar photovoltaic and lighting control provisions on a commercial job. This guide is written to make those conversations sharper, not to substitute for them.

Everything below reflects the published position at the date of writing. Adoption dates in particular have already moved once in several jurisdictions, and Tasmania reversed its adoption after it had commenced. The linked government sources are where to confirm the current position before you rely on a date.

What is the National Construction Code, and what does it actually bind?

The National Construction Code is a performance-based code produced by the Australian Building Codes Board that sets minimum requirements for the design and construction of buildings, plumbing and drainage systems. It is not law by itself. Each state and territory gives it legal effect through its own building and plumbing legislation, which is why the same edition can be mandatory in one jurisdiction and irrelevant in the next.

It runs to three volumes. Volumes One and Two are commonly referred to as the Building Code of Australia, and Volume Three as the Plumbing Code of Australia. Western Australia’s building regulator describes the structure this way and notes that Part 3 of the Building Act 2011 (WA) requires buildings to comply with building standards, with Part 4 of the Building Regulations 2012 prescribing what those standards are. Most jurisdictions work on the same pattern: an Act creates the compliance obligation, and subordinate legislation names the code.

Two practical consequences follow for a developer.

First, “performance-based” means there are generally two ways to comply. The deemed-to-satisfy provisions are prescriptive and cheap to certify. A Performance Solution is a bespoke demonstration that a design meets the Performance Requirement by another route, and it typically costs consultant time, carries certification risk, and can be a point of dispute at occupation. Where a code change makes the deemed-to-satisfy path more expensive, the Performance Solution path often becomes the thing your consultants argue about.

Second, because each jurisdiction adopts separately and varies the code, a design that complies in Melbourne may not comply in Sydney without change. State variations are published as an appendix to each volume, and they are not trivial in number. Victoria’s building regulator has said that the Victorian appendix to the 2025 edition reduces variations and additional clauses from 115 to 60 across the three volumes, which gives a sense of how much jurisdiction-specific overlay sat on the previous edition.

What changed in National Construction Code 2025?

The 2025 edition is a commercial and apartment edition. Residential detached housing was largely left alone by design, and the substantive new work sits in commercial buildings and in the common and shared parts of apartment buildings.

Building Ministers set the content at their meeting on 22 October 2025. The published communiqué records agreement to four adjustments for inclusion: “Water management in commercial and apartment buildings to prevent water ingress”, “Carpark fire safety provisions for commercial and apartment buildings”, “Commercial energy efficiency reforms including efficiency improvements and mandatory on-site solar photovoltaic systems to support net zero ambitions”, and “Condensation mitigation”.

Standards Australia’s summary of the edition adds a fifth area, structural reliability and fire safety Performance Solutions, and puts a little more detail on each. The Australian Building Codes Board publishes its own list of key changes, which is the place to work from once your consultants are into clause-level detail.

Water management in commercial and apartment buildings

The water management provisions strengthen requirements aimed at reducing water ingress risk in commercial and apartment buildings. Standards Australia describes them as “strengthened provisions for commercial and apartment buildings to reduce water ingress risk”.

For a residential apartment developer this is likely to be the single most consequential change in the edition, because waterproofing is already one of the most common sources of defect claims and rectification cost in Class 2 buildings. Tighter provisions could mean more substrate preparation, different detailing at penetrations and junctions, more inspection hold points, and more documentation at certification. None of that is expensive per square metre in isolation. It tends to become expensive when it lands on a trade package that was priced before the change, or when it adds inspections to a programme that was already tight.

Two jurisdictions have already varied it. New South Wales has said its package of variations will give “apartment building owners undertaking remedial building works the choice to utilise the waterproofing requirements set out in either the current edition of the NCC or the new NCC 2025”. The Australian Capital Territory has flagged that it will vary the edition so that existing buildings needing building approvals are exempt from the new waterproofing and drainage requirement. Both variations point the same way: the new provisions were seen as a real cost on remedial work.

Carpark fire safety

The edition updates fire safety provisions for carparks in commercial and apartment buildings. Standards Australia describes “enhanced requirements to address fire risks in shared and commercial carparking structures”.

Basement and podium carparks are already one of the more expensive parts of an apartment or commercial building per square metre, and fire safety provisions are the kind of change that can move a services budget rather than a finishes budget. Sprinkler coverage, mechanical ventilation and smoke management, and fire separation between the carpark and the levels above are the usual pressure points. Whether any of that bites on your job may depend heavily on building class, carpark size, and whether the design was already sprinklered.

The trap worth naming is sequencing. Carpark fire safety changes tend to show up in the hydraulic, mechanical and fire engineering packages, which are usually documented and priced early, and are awkward to reopen once a builder has a fixed price.

Commercial energy efficiency and mandatory on-site solar

This is the change with the clearest capital cost line attached to it. The Building Ministers’ communiqué records “mandatory on-site solar photovoltaic systems” as part of the commercial energy efficiency reforms. Standards Australia describes “new requirements such as improved lighting control requirements and mandatory on-site solar photovoltaic systems”.

For a developer building anything in the commercial classes, this generally moves solar photovoltaic from an optional environmental, social and governance line item into a compliance line item. That changes how it should be treated in a feasibility. A discretionary solar allowance can be value-managed out when the numbers get tight. A mandatory one cannot, and it also carries knock-on items that are easy to leave out of an early estimate: additional structural allowance for roof loading, switchboard and inverter space, metering, and the electrical infrastructure to connect it.

Lighting control changes are smaller in dollar terms but broader in reach, since they touch almost every tenancy and common area in a commercial building.

The size of the obligation is set by the code text and its state variations, so the number of kilowatts your specific building has to install is a question for your electrical engineer and energy consultant against the adopted volume in your jurisdiction, not something to assume from a headline. New South Wales has already said that under its variations “the new energy efficiency standards in the NCC 2025 will not apply to the common areas of apartment buildings”, which is a meaningful carve-out for residential apartment developers in that state.

Condensation mitigation

The edition changes condensation management provisions. Standards Australia notes the changes include “reduced ventilation requirements for small roofs”, which suggests the direction is not uniformly upward. Condensation provisions have been a moving target across recent editions, and they interact closely with insulation, wall wrap, cavity construction and roof ventilation.

The cost effect here is usually in the wall and roof build-up rather than in a single item, which makes it hard to isolate and easy to under-allow. It is also the change most likely to differ by climate zone, so a national rate carried across a portfolio may be misleading. Where a builder has a standard wall detail they use everywhere, a condensation change is exactly the kind of thing that produces a variation claim later.

Performance Solutions: structural reliability and fire safety

Standards Australia describes the change as clarifying assessment requirements so that Performance Solutions across structural and fire safety design are applied more consistently.

For a developer this is a documentation and process change rather than a materials change, but it is not free. Clearer assessment requirements generally mean more explicit evidence, more analysis, and a longer path through certification for any design relying on a Performance Solution. On a project where a Performance Solution is carrying a commercially important outcome, for example a fire engineered solution that avoids a second stair or preserves a floor plate, the risk is not the consultant fee. The risk is that the solution takes longer to land, or does not land in the form assumed at feasibility.

Victoria has published a clause-specific deferral worth knowing about: for combustible cladding Performance Solutions, the Victorian variation states that “the limitation above does not take effect until 1 year after adoption of NCC 2025”, which on Victoria’s 1 May 2026 adoption falls on 1 May 2027.

What did not change

Ministers agreed “there would be no further residential changes in NCC 2025, outside of essential safety and quality changes”. The communiqué records three specific things held over as a result: voluntary embodied carbon provisions were to be published as an Australian Building Codes Board guidance document rather than code, electric vehicle charging provisions were not introduced, and residential energy efficiency changes were not introduced. It also confirms that the approach “maintains the high energy efficiency standards adopted in NCC 2022, including 7-star energy efficiency”.

So the 7-star thermal performance requirement and the Whole of Home energy budget introduced in the previous edition remain the residential baseline. If you build houses and townhouses, the 2025 edition is unlikely to move your build cost much. If you build apartments, it reaches your common areas, your carpark and your waterproofing. If you build commercial, it reaches your roof.

Why is there a pause on residential changes until 2029?

Because the Commonwealth announced one on 24 August 2025, and Building Ministers agreed to it on 22 October 2025. The communiqué records that “no further residential changes to the NCC, except for essential quality and safety measures, will be made until mid-2029, following the finalisation of NCC 2025”, and that Ministers “agreed that the exemption would only apply to serious issues and changes that could not be deferred until the next edition of the code”.

For a developer with a residential pipeline, the practical read is that the residential build standard is expected to be stable for several years, which removes one variable from a long-dated feasibility. Land bought today for a project completing in 2029 has historically carried code-change risk that was hard to price. That risk has not disappeared, since essential safety and quality changes are still possible and state variations are unaffected by the pause, but it is narrower than it was.

Ministers also agreed to a programme to streamline the code, including looking at “the appropriate cadence of future NCC updates”. Cadence matters more than it sounds. A three-year cycle sets how often a long project can be caught by a transition, and any change to it would change how far ahead a developer needs to design.

When does National Construction Code 2025 apply in my state or territory?

Adoption is a matter for each jurisdiction, and as at the date of writing the positions differed materially. The communiqué is explicit that “the adoption of NCC 2025 is a matter for each jurisdiction”, and it already flagged that “Tasmania noted it has paused implementation of NCC 2025 measures”.

The summary below reflects the published government position at the date of writing. Because several of these dates have already moved, and one was reversed by legislation after it had commenced, treat the linked source as the answer rather than this table.

Victoria

Victoria adopted the edition on schedule. The Victorian government’s building standards page states that “Victoria will adopt the next edition of the National Construction Code (NCC 2025) on 1 May 2026”.

The transition is expressed in terms of when work started rather than as a grace period. The same page states that “the new NCC updates will only apply to projects that have not commenced design work until after 1 May 2026”, and that “projects that have already commenced construction or design when the new standards are adopted can continue to use the standards in place at the time work on the project commenced”. That is a softer test than a permit date, and it may be worth having your building surveyor confirm in writing how they are applying it to a project that straddles the change, because “commenced design work” is capable of more than one reading.

Two Victorian specifics are worth carrying into a feasibility. The Victorian appendix was cut from 115 variations to 60, which reduces the amount of Victoria-only detail a national builder has to carry. And Victoria has diverged on lead-free plumbing: the Building and Plumbing Commission notes that the national transition was extended to 1 May 2028 but that “Victoria has chosen to retain the earlier 1 May 2026 start date”, and that this “applies regardless of when a building permit was issued, or a contract was signed”. A plumbing package priced on national timing could be short in Victoria.

New South Wales

New South Wales deferred by a year. The Minister for Building announced on 25 March 2026 that “NSW will adopt the new National Construction Code (NCC 2025) on 1 May 2027”, describing it as a “12-month transition period” intended to “minimise future compliance risk and disruption to projects set to commence early next year”.

New South Wales also flagged a package of state variations, of which two were named in the release: the waterproofing choice for apartment remedial work described earlier, and the exclusion of the new energy efficiency standards from the common areas of apartment buildings. The release said information on all variations would be available when the full suite was published.

For a New South Wales apartment developer, the deferral plus those two variations together mean the edition’s cost impact in that state is likely to be materially lighter than the national headline suggests. That is worth checking rather than assuming, because the release describes the variation package at a high level and the operative detail sits in the published appendix.

Queensland

Queensland deferred by a year as well. The Queensland Building and Construction Commission’s published key dates are that “until 30 April 2027 - the NCC 2022 remains the mandatory standard for all building and plumbing work in Queensland” and “from 1 May 2027 - the NCC 2025 becomes the mandatory minimum standard across Queensland”.

Queensland’s position is a clean cutover rather than a period where either edition can be used, which makes the boundary easier to plan around but less forgiving for a project that slips across it.

South Australia

South Australia split the volumes. The state’s building code updates page states that “South Australia will adopt the Building Code within NCC 2025 on 1 May 2027”, that “South Australia adopted the Plumbing Code within NCC 2025 on 1 May 2026”, and that “NCC 2022 Amendment 2 will remain in force as the Building Code under the Planning, Development and Infrastructure Act 2016 until 30 April 2027”.

That split is easy to miss. A South Australian project designed in the window between those dates may be working to the new Plumbing Code and the old Building Code at the same time, which is a coordination point for the hydraulic consultant rather than a cost item as such.

Western Australia

Western Australia does not adopt editions by name and date the way the eastern states do. Its Building Regulations 2012 use a rolling reference. Regulation 31A provides that the applicable building standards are those “set out in the edition of the Building Code that is in effect at the time the application for the building permit is made” or “set out in the edition of the Building Code that was in effect 12 months before the time the application for the building permit is made”.

That look-back is a permanent mechanism, not a one-off concession for this edition, and it is genuinely useful to a developer. It generally gives a Western Australian project a twelve-month window in which either edition can be used, measured from the building permit application date. The regulations do name the newer edition, but in the Western Australian modification provisions, which repeatedly read “the Building Code (2022 and 2025 editions)”.

There is at least one carve-out from the look-back. Regulation 31A(2A) provides that the twelve-month option “does not apply to the building standards set out in the Building Code (2025 edition) Volume One Part G5 as modified by regulation 15D(2)”, which concerns construction in designated bushfire prone areas. Whether the look-back is available for a particular scope is a question for your building surveyor against the current consolidation, since these regulations have been amended several times.

Tasmania

Tasmania adopted the edition and then reversed it by legislation. The definition of “National Construction Code” in section 4(1) of the Building Act 2016 (Tas), as it stood at the date of writing, sets two periods.

Until 30 April 2027, the defined code is the edition “published by the Australian Building Codes Board entitled NCC 2022, and as last amended by NCC 2022 Amendment 2 on 29 July 2025”. On and from 1 May 2027, it becomes “the latest edition of that code published by the Australian Building Codes Board, including as amended, from time to time”.

Two things follow. Tasmania is back on the 2022 edition until 30 April 2027. And from 1 May 2027 the definition is a rolling one that picks up whatever the latest edition is at the time, rather than a fixed reference to the 2025 edition.

Whether there is a saving provision for building work approved during the short window when the newer edition applied in Tasmania is not apparent from the in-force Act text, so a Tasmanian project approved in that window is one to raise specifically with the building surveyor.

Australian Capital Territory

The Australian Capital Territory runs a nominated-version transition. Its planning directorate’s page states that “in the ACT, the NCC 2025 will commence on 1 May 2026 but will not be mandatory until May 1 2027”, and that projects with Building Approval in that window “may comply with either: NCC 2022 and the ACT 2022 Appendix, or NCC 2025 and the ACT 2025 Appendix”.

The important qualification is on the same page: “the version of the NCC that the project is complying with must be clearly nominated. A project cannot comply with a mix of regulations from each version.” Cherry-picking the cheaper clause from each edition is not available.

There is also a longer tail for projects already in the planning system. The page states that projects with a Development Application or Works Approval Application “formally lodged before 1 November 2026, may continue to seek Building Approval under either NCC 2022 or NCC 2025 until that Development Application expires”. For a Canberra project with a long approval path, that could be a meaningful extension of the older standard.

Northern Territory

At the date of writing, the Northern Territory did not appear to have brought the 2025 edition into effect, with the 2022 edition continuing to apply. The Territory’s position on which edition applies is set by declaration and published in the Northern Territory Government Gazette rather than on a policy page, so the gazette notice and the Territory’s building notes are where a Northern Territory developer would confirm the current position with their building certifier. This is the jurisdiction where the published position was hardest to verify from an accessible government page, so treat it as the one to check rather than assume.

Which edition applies to my project, and when does it lock in?

The edition that applies is generally fixed by a date attached to a statutory step, and the step is not the same in every jurisdiction. Getting this wrong is more expensive than getting the code content wrong, because it determines whether any of the new content applies to you at all.

Broadly, four different tests are in play across the country at the moment.

A commencement or design date. Victoria ties it to whether design or construction had commenced when the new standards were adopted. That is a factual test rather than a documentary one, which is convenient when a project is clearly underway and awkward when it is not.

A building permit or building approval application date. Western Australia’s regulation 31A ties it to the building permit application date, with the twelve-month look-back. The Australian Capital Territory ties its nominated-version window to Building Approval, with the extra tail for projects with a Development Application lodged before 1 November 2026.

A hard cutover date. Queensland’s published dates operate as a clean switch on 1 May 2027.

A statutory definition that moves. Tasmania’s Act defines the code by date ranges, and from 1 May 2027 the definition becomes a rolling reference to the latest edition.

Two implications are worth building into how you plan a project.

First, the lock-in point is usually earlier than construction. On a project running through a Development Application, a Construction Certificate or building permit, and then construction, the edition is generally settled well before a builder is on site. That means the design consultants, not the builder, are the ones who need to know which edition they are documenting to, and they need to know before documentation is complete, not after.

Second, the transition window is a programme risk with a cost attached. If a project sits close to a cutover and the approval slips, the consequence can be a redesign to a different standard, priced at a different rate, on a job whose land price and development margin were set on the older assumption. Where a deal is close to a cutover, it is generally the kind of thing worth running as a separate scenario rather than as a contingency line.

What does National Construction Code 2025 do to build cost?

There is no reliable single answer, and any guide quoting one figure across all building types should be read carefully. The honest position is that the cost effect depends on building class, jurisdiction, climate zone and what the design already did voluntarily. What can be said usefully is where the cost sits and who can price it.

For a commercial building, the identifiable new capital items are likely to be the on-site solar photovoltaic system and its supporting infrastructure, lighting control upgrades, and whatever the carpark fire safety provisions require above the previous baseline. Solar is the one most likely to be a genuinely new line rather than an uplift on an existing line.

For an apartment building, the pressure is more likely to be on waterproofing and water management detailing, the carpark, and condensation-driven changes to the wall and roof build-up. These tend to show up as rate increases spread across trade packages rather than as a new line item, which makes them easier to miss in a high-level estimate and harder to argue about later.

For detached housing and townhouses, the edition is largely a non-event, given the residential pause and the retention of the previous edition’s 7-star and Whole of Home requirements.

Three practical points sit underneath that.

The first is who prices it. A quantity surveyor working from a cost plan built on 2022 edition rates will produce a number that is right for the wrong edition unless someone tells them which edition the project will be certified under. That instruction is cheap to give and expensive to forget. Where a project is close to a cutover, comparing the two editions as separate scenarios is generally more useful than adding a single allowance, and it is the kind of comparison a feasibility model with scenario tooling handles better than a duplicated spreadsheet, since the difference flows through to total development cost rather than sitting in one cell.

The second is the base rate. Any construction cost per square metre benchmark you are carrying was derived from projects built to a particular edition. Benchmarks lag code changes, sometimes by years, so a rate that looks current may be describing a building that would not comply today.

The third is contingency. A code transition is exactly the kind of known unknown that construction contingency exists for, but treating it purely as contingency has a downside: contingency gets consumed by other things, and a mandatory solar system is not a risk, it is a certainty with an unknown size. Separating the two may give a cleaner picture of where the project actually sits.

How does the code interact with your building contract and programme?

The question that decides who pays is usually whether the contract treats a code change as a change in law, and whether the change happened before or after the relevant date in the contract.

Most standard-form Australian building contracts contain a change in law or statutory requirement mechanism that entitles the contractor to a variation where a legislative requirement changes after a nominated date, often the date of the contract or the date for pricing. Whether an adoption of a new edition of the code triggers that clause on your contract is a question of the specific wording, the nominated date, and what the contractor was told to price. It is not a question with a general answer, and it is worth putting to your construction lawyer before signing rather than after a claim arrives.

Delivery model changes the exposure. Under a design and construct contract, the contractor generally takes design responsibility, which can include responsibility for compliance with the code, but the allocation depends on what the design brief specified and whether it named an edition. A brief that says “comply with the National Construction Code” without naming an edition may behave differently from one that names the 2022 edition. Under a guaranteed maximum price contract, the same question arises inside the cost ceiling, and the interesting issue becomes whether a code-driven increase eats the contingency inside the guaranteed maximum price or sits outside it.

On programme, the point of exposure is the certification path rather than the build. If the applicable edition changes between design completion and approval, the resubmission is usually the delay, and delay on a development is rarely just time. It is holding cost, and it moves the development cashflow profile. A project sitting close to a jurisdictional cutover may be worth programming backwards from the approval date rather than forwards from the start date.

Does the National Construction Code apply in New Zealand?

No. New Zealand has its own building code, made under the Building Act 2004 (NZ) and administered by the Ministry of Business, Innovation and Employment. It works on a similar performance-based logic, with performance clauses supported by Acceptable Solutions and Verification Methods, but the clauses, the numbering and the technical content are separate from the Australian code. An Australian consultant team working across the Tasman cannot carry Australian deemed-to-satisfy detailing into a New Zealand project.

For a New Zealand developer, the equivalent moving parts are the annual building code updates and the energy efficiency clause. The Ministry publishes the H1 energy efficiency requirements and their supporting Acceptable Solutions and Verification Methods, and its maintaining the Building Code pages set out what changed and when.

The H1 timeline is worth noting if you are building on both sides of the Tasman, because it does not line up with the Australian cycle. The Ministry’s published current versions of the H1 Acceptable Solutions and Verification Methods took effect on 27 November 2025, the previous editions run until 26 November 2026, and the Ministry has flagged that “from 27 November 2026, a number of changes to the H1 Energy Efficiency Acceptable Solutions and Verification Methods will come into effect”. Building Code compliance in New Zealand sits alongside, not inside, the resource consent process, which deals with land use rather than construction standards.

Some Australian Standards are joint Australian and New Zealand standards and are referenced in both systems, which is a source of confusion. A shared standard does not mean a shared code.

What to ask your building surveyor and quantity surveyor

The questions below are the ones that decide the answer on your specific project. They are deliberately not answered here, because the answers depend on your jurisdiction, your building class and your approval dates.

For the building surveyor or principal certifier

• Which edition of the National Construction Code will this project be assessed under, and what is the statutory step and date that fixes it?
• If the project slips past that date, does the applicable edition change, and what would have to be redesigned?
• Which state or territory variations apply to this building class, and which of them differ from the national provisions in a way that affects the design?
• Are we relying on any Performance Solutions, and do the revised assessment requirements change the evidence needed to support them?
• For a Western Australian project, is the twelve-month look-back in regulation 31A available for this scope, or does a carve-out apply?
• For an Australian Capital Territory project, which version are we nominating, and does the Development Application lodgement date extend our options?
• For a Tasmanian project approved during the window when the newer edition briefly applied, which edition governs now?

For the quantity surveyor

• Which edition of the code is the cost plan priced against, and does that match the edition the certifier will assess?
• What is the delta between the two editions for this building, broken down by trade package rather than as a single allowance?
• What have you allowed for the on-site solar photovoltaic system, including structural allowance for roof loading, switchboard and inverter space, metering and connection?
• What have you allowed for the carpark fire safety provisions, and does that assume the building was already sprinklered?
• Are the benchmark rates in this cost plan derived from projects built to the current edition or the previous one?

For the builder and the construction lawyer

• Does the contract contain a change in law or statutory requirement mechanism, what date does it run from, and would an adoption of a new code edition trigger it?
• What edition was the tender priced against, and is that recorded anywhere in the contract documents?
• Under the design brief, who carries responsibility for compliance if the applicable edition changes during design?
• If a code change produces a variation, does it sit inside or outside the contingency, and inside or outside any guaranteed maximum price?

For the energy and sustainability consultant

• What size solar photovoltaic system does this building actually need to comply, and what are the constraints on the available roof area?
• Do the lighting control requirements change the electrical design or just the specification?
• What do the condensation provisions do to the wall and roof build-up in this climate zone, and does that change the insulation or cladding selection?

The theme running through all of these is the same. The code content is public and your consultants can read it. What they cannot read from a website is which edition binds your project, and that is the question that decides whether any of it costs you anything at all.