Author: Franz Phan, Senior Planning Consultant, giantA Pty Ltd (15+ years experience in NSW residential and multi-unit development)
Introduction: Why the NCC Freeze Matters for NSW Builders and Homeowners
In October 2025, Australia's Building Ministers formally agreed to pause further residential energy efficiency changes to the National Construction Code (NCC) until at least mid-2029. The decision followed the Commonwealth Minister for Housing's announcement in August 2025 and was confirmed once NCC 2025 was finalised. For anyone planning a residential build or renovation in New South Wales, this pause creates a period of regulatory certainty that is rare in construction — but it also raises genuine questions about how it interacts with NSW's own BASIX framework, which sits alongside the NCC rather than inside it.
The practical reality is that the 7-star NatHERS thermal standard and Whole of Home energy budget introduced under NCC 2022 remain the baseline for the rest of the decade. No further residential energy efficiency requirements will be added to the national code before mid-2029, with exceptions only for essential safety and quality measures. However, BASIX is a state-level instrument administered by the NSW Government under the Sustainable Buildings SEPP, and the NCC freeze does not bind it. NSW could still update BASIX independently, though no such changes are currently flagged.
This article breaks down exactly what the freeze covers, why BASIX sits outside it, what NCC 2025 does change (commercial and condensation provisions), and what homeowners, developers, and builders in NSW should plan for through to 2029.
What the NCC Energy Efficiency Freeze Actually Covers
The freeze applies specifically to residential energy efficiency provisions within the NCC itself. In practice, this means no new residential thermal performance, Whole of Home, or energy-related requirements will be added to the national code before mid-2029. The 7-star NatHERS-equivalent thermal standard and the Whole of Home energy budget (60 out of 100 for houses, 50 out of 100 for apartments under NCC default settings) introduced in NCC 2022 remain the framework for the foreseeable future.
NCC 2025, published in February 2026 with state-by-state adoption from May 2026, was deliberately narrowed in scope. Its changes are concentrated in commercial buildings, water ingress management, carpark fire safety, mandatory on-site solar for commercial buildings, and condensation mitigation. Residential energy efficiency provisions that might otherwise have appeared in NCC 2025 were explicitly excluded and deferred under the freeze.
For context, the average Australian home rated approximately 1.8 stars in 2003 when no national minimum existed. The 6-star floor was mandated nationally from 2010, before NCC 2022 lifted it to 7 stars and added the Whole of Home budget — a bigger shift than the one-star headline suggests. The current pause means the industry now has until at least mid-2029 to bed down the 7-star standard before any further uplift is considered.
NCC Timeline: From 6 Stars to the 2029 Freeze
| Period | Standard | Key Change |
|---|---|---|
| 2003 | ~1.8 stars (average existing home) | No national minimum |
| 2010 | 6 stars (NatHERS) | First national mandatory minimum |
| Oct 2023 (NSW) | 7 stars + BASIX uplift | BASIX aligned with NCC 2022; 7–11% GHG reduction increase |
| May 2026 | NCC 2025 adopted (commercial only) | No new residential energy provisions |
| Mid-2029 | Earliest review | Building ministers to consider further residential changes |
Is BASIX Affected by the NCC Freeze?
No, BASIX is not directly affected by the NCC freeze. This is one of the most common points of confusion among NSW builders and homeowners. The National Construction Code is a national model code adopted state by state, while BASIX is a standalone NSW planning requirement under the Sustainable Buildings SEPP (State Environmental Planning Policy). They are governed by entirely separate processes — a change or freeze affecting one does not automatically affect the other.
BASIX predates the current NCC energy provisions. It was introduced on 1 July 2004 as a NSW government initiative to reduce water consumption by 40% and greenhouse gas emissions by 45% by 2030, while improving thermal comfort in residential dwellings. The 2023 uplift aligned BASIX's thermal performance standard with the NCC 2022 7-star equivalent, increased GHG emission reduction targets by 7–11% depending on location and development type, and introduced a materials index to measure embodied emissions in construction materials.
The NCC freeze prevents new residential energy efficiency requirements from being added to the national code before mid-2029. It does not wind back anything already required, and it does not prevent the NSW Government from updating BASIX independently. In practice, no BASIX changes are currently flagged as a result of the freeze, but the legal separation means NSW builders should not treat BASIX as frozen simply because the NCC is.
BASIX vs NCC: Key Differences
| Feature | BASIX (NSW) | NCC (National) |
|---|---|---|
| Jurisdiction | NSW only | National model code, adopted state by state |
| Legislation | Sustainable Buildings SEPP, EP&A Act 1979 | Building Code of Australia (BCA) |
| Scope | Energy, water, thermal comfort, materials index | Energy efficiency, structural, fire, health, amenity |
| Freeze status | NOT frozen — NSW can update independently | Frozen for residential energy until mid-2029 |
| Current thermal standard | 7-star NatHERS equivalent (since Oct 2023) | 7-star NatHERS (NCC 2022) |
| When can it change? | Any time NSW Government decides | No earlier than mid-2029 |
What NCC 2025 Actually Changes (and What It Doesn't for Residential)
NCC 2025 was published in February 2026, with state-by-state adoption beginning May 2026. Its residential energy efficiency provisions were deliberately excluded under the freeze, so the 7-star standard and Whole of Home budget remain unchanged. What NCC 2025 does change is primarily relevant to commercial and multi-residential construction:
Commercial building reforms include mandatory on-site solar for certain commercial buildings, enhanced water ingress management, and improved carpark fire safety provisions. Condensation mitigation provisions have been strengthened across both commercial and residential, addressing moisture management in wall cavities and roof spaces — this is the one area where residential construction sees changes under NCC 2025, though it relates to moisture and durability rather than energy efficiency per se.
Adoption timelines vary by state. Victoria, Western Australia, and the ACT adopted NCC 2025 from 1 May 2026. NSW and Queensland deferred mandatory adoption to 1 May 2027, with early voluntary adoption available in the meantime. Because NCC 2025's energy-related changes are commercial-focused, this staggered rollout has no bearing on residential BASIX obligations in NSW — homeowners and builders working on houses can safely disregard the adoption timeline when planning a residential project.
What This Means for Homeowners Planning a Build or Renovation
For homeowners, the freeze provides something increasingly valuable in construction: certainty. If you are planning a new build or a renovation costing $50,000 or more in NSW, the BASIX requirements you need to meet today are the same ones that will apply through to at least mid-2029 at the national level. There is no reason to delay a project in the hope that requirements might become less stringent — they will not, and waiting only pushes back your approval and construction timeline without any compliance benefit.
The current BASIX standards require a 7-star NatHERS-equivalent thermal performance rating for new single dwellings, a 7–11% improvement in greenhouse gas emission reduction targets depending on your location and development type, and compliance with the materials index for embodied emissions reporting. A BASIX certificate is mandatory before a Development Application (DA) or Complying Development Certificate (CDC) can be lodged, assessed, or approved.
The NSW Government's own modelling estimates that a home meeting the higher BASIX standard saves an average of $1,070 per year in energy bills. Upfront construction cost increases vary by location and dwelling type: approximately $7,152 for a house in Blacktown, $6,403 for a townhouse in Albion Park, and $860 per unit for a high-rise apartment in Macquarie Park. These costs are typically recovered within 7–10 years through energy savings, with the payback period shorter for larger homes in cooler climate zones.
What This Means for Developers and Builders
For developers and builders, the freeze means standardised house designs and specifications that meet the current 7-star standard will remain compliant through to mid-2029 at the national level. This reduces the need for frequent design updates and allows volume builders to optimise their standard plans for the current requirements rather than chasing a moving target.
However, there are important nuances. BASIX is not frozen — the NSW Government could still update it independently, though no changes are currently planned. Builders should also be aware that NCC 2025's condensation mitigation provisions, which do affect residential construction, are being adopted in NSW from 1 May 2027. These provisions relate to moisture management in building envelopes rather than energy efficiency, but they may require adjustments to wall construction details, vapour barriers, and roof ventilation.
The May 2026 BASIX tool upgrades, which introduced the Passive House Standard method as an alternative compliance pathway for thermal performance, remain available and are not affected by the freeze. This gives builders and designers additional flexibility in how they demonstrate BASIX compliance, particularly for projects pursuing high-performance or passive house outcomes.
Key Compliance Actions for Builders Through 2029
| Action | Timing | Reason |
|---|---|---|
| Ensure all standard designs meet 7-star NatHERS | Now | Current requirement, no change expected before mid-2029 |
| Monitor NCC 2025 condensation provisions | Before May 2027 (NSW) | New moisture management requirements for residential |
| Consider Passive House Standard method | Optional | Alternative BASIX thermal performance pathway |
| Track any NSW BASIX updates independently | Ongoing | BASIX is NOT frozen — NSW can update separately |
| Maintain BASIX certificate process for all projects | Every project | Mandatory for DA/CDC lodgement |
Real Project Example: Navigating the Freeze on a Dual Occupancy in Parramatta
A recent giantA project involved a dual occupancy development in Parramatta where the client initially considered delaying their DA submission in anticipation of potential regulatory changes. After reviewing the NCC freeze announcement and confirming with the local certifier that BASIX requirements were stable, the client proceeded with the current 7-star standard. The project achieved BASIX compliance through a combination of improved glazing (double-glazed windows with low-E coating), increased ceiling insulation (R6.0), and a 5kW solar PV system. The total BASIX-related cost premium was approximately $9,200 across both dwellings, with modelled energy savings of $1,140 per year — a payback period of just over 8 years. Had the client waited, construction costs would have increased by approximately 4–6% due to material price inflation, with no regulatory benefit.
What Happens After Mid-2029?
Building ministers will consider further residential energy efficiency changes from mid-2029 onwards. The direction of any future changes is not yet determined, but industry consultations and government modelling suggest the conversation will likely focus on whether to move towards an 8-star thermal standard, expand the Whole of Home budget scope, or introduce additional embodied carbon requirements. The materials index introduced under BASIX in 2023 may also be expanded to cover a broader range of materials and life-cycle stages.
For now, the focus for NSW builders and homeowners should be on bedding down the current 7-star standard, optimising designs for cost-effective compliance, and taking advantage of the regulatory stability to refine standard plans and construction details. The freeze is an opportunity to consolidate expertise and deliver homes that perform well without the uncertainty of imminent regulatory change.
Frequently Asked Questions
Is BASIX going away because of the NCC freeze?
No. BASIX is a standalone NSW planning requirement under the Sustainable Buildings SEPP, completely separate from the NCC. The freeze on national code changes does not affect BASIX, which remains mandatory for all new residential dwellings, renovations over $50,000, and pools over 40,000 litres in NSW. A BASIX certificate is still required before any DA or CDC can be lodged.
Will the 7-star energy standard change before 2029?
No. Building ministers agreed in October 2025 to pause further residential energy efficiency changes to the NCC until at least mid-2029. The 7-star NatHERS-equivalent thermal standard and Whole of Home energy budget introduced under NCC 2022 remain the baseline. However, NSW could still update BASIX independently, though no such changes are currently planned.
Should I delay my building project to wait for regulatory changes?
No. There is no compliance reason to delay. Current BASIX requirements are stable and will remain in place through to at least mid-2029 at the national level. Waiting only increases construction costs due to material price inflation and pushes back your approval and construction timeline. Proceed with the current 7-star standard.
Does NCC 2025 introduce any new residential energy requirements?
No. NCC 2025, published February 2026, deliberately excluded residential energy efficiency provisions under the freeze. Its changes focus on commercial buildings, water ingress, carpark fire safety, and condensation mitigation. NSW adopts NCC 2025 mandatory provisions from 1 May 2027, but this has no bearing on residential BASIX obligations.
Can the NSW Government still change BASIX during the freeze?
Yes. The NCC freeze does not bind the NSW Government. BASIX is governed by state planning legislation and can be updated independently at any time. However, no BASIX changes are currently flagged as a result of the national freeze, and the NSW Government has indicated it is focused on bedding down the current standards.
How much does BASIX compliance add to construction costs?
BASIX-related cost increases vary by location and dwelling type. NSW Government modelling estimates approximately $7,152 for a house in Blacktown, $6,403 for a townhouse in Albion Park, and $860 per unit for a high-rise apartment in Macquarie Park. These costs are typically recovered within 7–10 years through energy savings averaging $1,070 per year.
Does the NCC freeze affect the Passive House Standard method for BASIX?
No. The Passive House Standard method, introduced as an alternative BASIX thermal performance compliance pathway in May 2026, is a NSW state-level initiative under BASIX. It is completely independent of the NCC freeze and remains available for qualifying projects in eligible NSW locations. The freeze has no impact on this pathway.
What should builders do differently during the freeze period?
Builders should use the regulatory stability to optimise standard house designs for the current 7-star standard, refine construction details for cost-effective compliance, and prepare for NCC 2025 condensation provisions adopting in NSW from May 2027. There is no need to design for hypothetical future standards — the focus should be on delivering current requirements efficiently.
About the author: Franz Phan is Senior Planning Consultant at giantA Pty Ltd, a NSW-based construction and building company specialising in residential, multi-unit, and sustainable development. With over 15 years of experience navigating NSW planning and building regulations, Franz has overseen more than 200 BASIX-compliant projects across Sydney and regional NSW.
Sources: NSW Planning Portal (planningportal.nsw.gov.au), Australian Building Codes Board (abcb.gov.au), Department of Climate Change, Energy, the Environment and Water (DCCEEW), Sustainable Buildings SEPP, BuildStreet energy efficiency analysis (July 2026), ABS Building Approvals data (May 2026).
Contact giantA: Visit [gianta.com.au](https://gianta.com.au) or call (02) 9891 8882 to discuss your BASIX compliance, development application, or sustainable building project with our team.