The National Construction Code 2025 (NCC 2025) is now in effect in the ACT as of 1 May 2026, with full mandatory adoption from 1 November 2026. If you're planning a new build, extension or significant renovation in Canberra, this is one of the most consequential regulatory shifts in years, and Master Builders ACT estimates it will add anywhere from $14,000 to $55,000 to a typical new home.
I'm Jeff Rentoule, director of Rentoule Projects. We've been getting a lot of questions about NCC 2025 from Canberra homeowners over the past few weeks. This article walks through what's actually changed, who it affects, what it adds to your project, and how to plan around it.
What is the NCC and why does it matter?
The National Construction Code is the technical document that governs how buildings are built in Australia. It covers structural requirements, fire safety, health and amenity, energy efficiency, and accessibility. Every three years, the Australian Building Codes Board (ABCB) releases an updated version, and each state and territory decides when and how to adopt it.
The current version, NCC 2022, has been in force across most of Australia since May 2023. NCC 2025 was published in 2025 and most states began transitioning into it through late 2025 and 2026. The ACT formally adopted NCC 2025 from 1 May 2026, with a six-month transition window where builders can choose either NCC 2022 or NCC 2025 for projects with Building Approval issued before 1 November 2026. From 1 November 2026, NCC 2025 is mandatory for all new applications.
If your renovation, extension or new build requires a Building Approval (and most do), the NCC version that applies is determined by when that approval is lodged.
The headline change: stricter energy and accessibility requirements
NCC 2025 is not a wholesale rewrite. The structural and fire safety provisions look very similar to NCC 2022. The areas where it bites hardest for residential building are energy efficiency and livable housing (accessibility).
Energy efficiency
NCC 2022 already lifted the minimum energy efficiency rating for new homes from 6 stars to 7 stars, plus introduced a "whole of home" annual energy use budget. NCC 2025 maintains those baselines but tightens compliance pathways and adds new options that weren't previously available, including:
- Updated NatHERS modelling methods for alterations and extensions to existing homes
- A new Passivhaus pathway for builders who want to certify against that international standard
- Mandatory blower-door testing in some compliance pathways to verify air tightness
- More prescriptive requirements for fixed mechanical heating and cooling systems
For most Canberra renovations and extensions, the practical effect is that the energy performance modelling becomes more rigorous, and the building envelope (insulation, glazing, air sealing) needs to be specified more carefully. A standard double-glazed window in NCC 2022 might not pass NCC 2025 modelling depending on orientation and the rest of the building. We covered the EER framework in our guide to EER ratings in Canberra, and NCC 2025 builds directly on top of that.
Livable housing
NCC 2022 introduced the Livable Housing Design standard for new dwellings, which mandated step-free entry, wider doorways, accessible bathroom facilities and structural reinforcement for future grab-rail installation. NCC 2025 carries this forward with refined definitions and slightly stricter compliance paths.
For new builds, this typically translates to wider hallways, larger ground-floor bathrooms, accessible thresholds, and slab penetrations sized for future installation. None of it is dramatic, but it does add square metres to certain rooms, which adds cost.
What does it actually mean for your Canberra project?
The honest answer depends on what you're doing.
If you're building new
NCC 2025 applies to your build in full if your Building Approval is issued from 1 November 2026 onwards, and applies as an option (alongside NCC 2022) for the six months before that. The financial impact is real: Master Builders ACT has estimated $14,000 to $55,000 in additional cost on a typical new home, depending on size, design, and how much of the existing specification was already meeting NCC 2025 standards.
Most of that cost lands in three places. First, higher-performance glazing (low-e double or triple glazed). Second, more rigorous insulation and air-sealing detail. Third, the slightly larger floor plan needed to accommodate Livable Housing minimums. None of it is wasted money, but it does need to be in your budget from day one.
If you're extending
This is the bit that catches people out. Extensions over a certain threshold trigger NCC 2025 energy compliance for the new addition, and depending on size, can also trigger upgrade requirements for parts of the existing dwelling. The NatHERS modelling pathway for extensions has been updated under NCC 2025, which can change the result for projects on the boundary.
If you're planning an extension in suburbs like Ainslie, Yarralumla, Griffith or Campbell, the existing home is often a 1950s or 1960s build with minimal insulation and single-glazed windows. NCC 2025 doesn't generally force you to upgrade the whole house, but it will force the new section to perform to current standards, and the way the two halves are modelled together matters.
If you're renovating internally
For most internal renovations that don't change the building footprint or alter external thermal performance significantly, NCC 2025 has minimal impact. A new bathroom, a new kitchen, internal layout changes, replacement of finishes - these typically don't trigger NCC 2025 energy compliance. Plumbing, electrical and structural rules apply as normal, and the Plumbing Code of Australia 2025 also commenced in the ACT on 1 May 2026 with its own transition arrangements.
What if my project is already in design?
If you have a project where Building Approval is likely to be lodged before 1 November 2026, you have a choice. You can elect to use NCC 2022, which keeps the existing design largely as-is. Or you can elect NCC 2025, which adds cost but futureproofs the build.
For most Canberra clients, my advice has been to stay with NCC 2022 if you're already deep into design and ready to lodge. But if you're at the early concept stage and not lodging until late 2026 anyway, design to NCC 2025 from the start. Trying to retrofit NCC 2025 compliance onto a NCC 2022 design halfway through the process is more expensive than designing for it from the outset.
How does this fit with the wider cost picture?
NCC 2025 is landing on top of construction costs that are already under pressure. The Middle East conflict that started in February 2026 has driven diesel and shipping costs up, with flow-on effects for materials. The latest ABS Producer Price Index data shows building materials up 2.5% year on year, with new house costs up 4.1% and electrical equipment up 6.3%. These are not small numbers when stacked on top of NCC 2025 transition costs.
For a Canberra new build that might have cost $850,000 in early 2025, the same project today is likely to come in around $920,000 to $980,000 once NCC 2025 compliance, materials inflation, and the current diesel-driven freight surcharges are accounted for. We covered the conflict-driven cost shifts in detail in our analysis of Middle East conflict impacts on Australian construction.
If you're at quote stage, ask your builder explicitly whether the price reflects NCC 2022 or NCC 2025. The answer affects what's actually in the contract.
What we're doing at Rentoule Projects
For all new projects entering design from May 2026 onwards, we're designing to NCC 2025 unless the client specifically requests otherwise. For projects already in design that we expect to lodge before November, we're holding to NCC 2022 to avoid mid-stream redesign costs but flagging the NCC 2025 path as an option.
Every fixed-price contract we offer makes the NCC version explicit. Every quote includes the energy and accessibility specification we're committing to. There are no surprises mid-build because the compliance pathway is locked in before we sign.
Frequently asked questions
Does NCC 2025 apply to renovations of older homes?
For most internal renovations, no. NCC 2025 energy requirements typically only apply when you're adding new floor area or significantly altering the external building envelope. A new kitchen, bathroom or internal reconfiguration in an existing 1960s Canberra home generally doesn't trigger NCC 2025 energy provisions, although standard structural, electrical and plumbing rules still apply.
How much will NCC 2025 add to my new build cost?
Master Builders ACT estimates $14,000 to $55,000 on a typical new home, depending on the design, finishes, and how much of the existing specification was already at NCC 2025 standard. Most of that lands in higher-performance glazing, tighter insulation detailing, and the larger floor plan needed for Livable Housing minimums. Get a builder to quote both pathways if you have flexibility on timing.
What's the difference between NCC 2022 and NCC 2025?
NCC 2022 introduced 7-star minimum energy efficiency and the Livable Housing standard for new homes. NCC 2025 maintains those baselines but updates the compliance pathways with stricter modelling methods, new options like Passivhaus certification, and refined accessibility provisions. The structural and fire safety provisions are very similar to NCC 2022.
Can I still use NCC 2022 for my Canberra build?
Yes, but only if your Building Approval is lodged before 1 November 2026. From 1 May 2026 to 31 October 2026, ACT builders can elect either NCC 2022 or NCC 2025 for new applications. From 1 November 2026 onwards, NCC 2025 is mandatory. The pathway is locked in at the time of Building Approval, not at construction start.
Does my extension need to comply with NCC 2025?
If your extension's Building Approval is lodged after 1 November 2026, yes - the new addition must comply with NCC 2025. Depending on the size of the extension and the existing dwelling's performance, parts of the existing home may also need upgrades. The NatHERS modelling pathway for extensions has changed under NCC 2025, so projects on the compliance boundary may see different results compared to NCC 2022.
Plan your project with the regulations in mind
NCC 2025 is not a reason to abandon a project, and it's not a regulation designed to make building unaffordable. It's a tightening of the standards we apply to make new homes warmer in winter, cooler in summer, more accessible as we age, and better aligned with the long-term emissions reduction direction the country is heading.
What it does mean is that getting good advice up front, locking in your compliance pathway early, and having a builder who actually understands what's changing is more valuable than ever. If you're planning a renovation, extension or new build in Canberra and want a straightforward conversation about what NCC 2025 means for your project specifically, get in touch with Rentoule Projects. We'll walk you through the compliance options, give you a realistic cost picture, and help you make a decision that fits your timeline and budget.