Building a townhouse in Melbourne has never been a simple exercise. Between council overlays, rising construction costs, planning delays, and changing energy rules, plenty of developers already feel like they are trying to hit a moving target. Now, the upcoming NCC 2026 changes are adding another layer to the equation.
From May 2026, new townhouse builds across Victoria will need to meet stricter standards around energy efficiency, accessibility, and moisture control. These changes will increase upfront construction costs. There is no way around that. But there is also a bigger picture that many people miss during the early planning stage.
At MJS Construction Group, we have spent more than 35 years building homes and townhouse developments across Melbourne’s Bayside and inner suburbs. We are already seeing these new standards shape design conversations long before permits are lodged. Some clients walk into our office worried they will need to slash their project scope. Others assume the changes are just “more paperwork.” The truth sits somewhere in the middle.
The projects that handle these changes best are the ones planned properly from day one.
Why NCC 2026 Will Change the Way Melbourne Townhouses Are Built
The New Rules Begin in May 2026
Victoria is expected to adopt the updated National Construction Code from May 1, 2026. That date matters. A lot.
Projects approved before the transition may still fall under earlier NCC rules, while projects lodged later could need full compliance with the updated standards. Timing now plays a much bigger role in construction budgeting.
We recently spoke with a townhouse developer in Bentleigh who assumed his dual occupancy project would squeeze through under the older code. Delays in town planning pushed the application back several months. Suddenly, the entire energy strategy had to change halfway through documentation. That meant redesign costs, revised engineering, and upgraded glazing specifications.
That sort of domino effect can snowball quickly if the project team is not paying attention early.
Why the Government Is Tightening Residential Building Standards
The changes are largely driven by three issues:
- Rising energy costs
- Housing accessibility
- Condensation and mould problems in modern homes
Melbourne’s climate plays a big role here. Anyone who has lived through a Bayside winter knows how cold poorly insulated homes can become. Older townhouses with single glazing and minimal wall insulation often feel like sieves once the temperature drops.
The new standards aim to create homes that are:
- Cheaper to run
- Healthier to live in
- More comfortable year-round
- Easier to access as owners age
As builders, we can see why these changes are happening. We also understand why some clients feel nervous about the extra cost.
The 7-Star Energy Rating Will Push Build Costs Higher
Double Glazing Is Quickly Becoming Standard
Under NCC 2026, achieving a 7-star NatHERS rating will become far tougher without better-performing windows.
For many townhouse projects, double glazing is now the bare minimum.
Years ago, double glazing was viewed as a luxury upgrade. Today, it is becoming standard practice across Melbourne developments, especially in suburbs close to major roads, train corridors, and high-density precincts.
| Window Type | Approximate Cost Impact | Energy Performance |
| Single Glazed | Lower upfront cost | Lower thermal efficiency |
| Double Glazed | Higher upfront cost | Improved insulation and noise reduction |
One client in Hampton initially resisted upgrading to double glazing because of the added expense. Six months after moving in, they admitted the quieter interiors and lower heating bills made the investment worthwhile. Sometimes the penny drops after people actually live in the home.
Insulation Requirements Are Increasing Across the Board
The new code also requires stronger thermal performance in:
- Walls
- Ceilings
- Floors
- Roof spaces
This means higher insulation R-values and tighter building envelopes.
On compact townhouse sites, every small design decision now matters. Oversized windows facing west, poor shading, or awkward orientation can force builders into expensive upgrades later just to pass energy assessments.
A smart design at concept stage can save thousands during construction.
All-Electric Homes Are Becoming More Common
Many townhouse developments are moving away from gas entirely to meet whole-of-home energy targets.
Common inclusions now include:
- Heat pump hot water systems
- Solar panels
- LED lighting
- Reverse-cycle heating and cooling
- Induction cooktops
This shift can increase upfront costs, but operational savings are substantial over time.
Victorian households are already dealing with rising utility bills. A better-performing townhouse helps soften that blow.
Livable Housing Requirements Will Reshape Townhouse Layouts
Step-Free Access Sounds Simple Until You Build on a Sloping Block
One of the biggest NCC 2026 changes involves mandatory accessibility requirements under the Livable Housing Design Guidelines.
That includes:
- Step-free entry
- Wider hallways
- Accessible bathrooms
- Ground-floor toilet circulation space
On flat land, these changes are manageable. On sloping Melbourne sites, things get trickier fast.
We worked on a concept townhouse design in Glen Iris where achieving compliant step-free access required significant regrading near the front entry. The additional retaining work alone added thousands to the site budget before construction even began.
That is why site analysis matters so much early.
Wider Hallways and Doors Affect More Than People Realise
Accessibility rules require wider openings throughout the home.
That sounds minor on paper. In reality, wider corridors and door clearances can affect:
- Structural framing
- Stair layouts
- Joinery sizing
- Bathroom positioning
- Overall floor area efficiency
On narrow townhouse lots, space is already tight as a drum. Losing even a small amount of usable area can trigger larger redesign discussions.
Future-Proofing Is Becoming a Stronger Selling Point
There is another side to this conversation.
Many buyers now actively look for homes they can age into comfortably. Young families also value layouts that work for prams, injuries, or older relatives visiting regularly.
Features that once felt unnecessary are becoming selling points.
Livable Housing Features Required Under NCC 2026
- Step-free entry
- Wider doorways
- Ground-floor accessible toilet
- Reinforced bathroom walls
- Step-free shower access
Retrofitting these features later often costs far more than including them during construction.
Ventilation Rules Are Tightening Because Airtight Homes Create New Problems
Better-Sealed Homes Need Better Ventilation
Modern homes are becoming far more airtight. That improves energy performance, but it also traps moisture inside the building.
Without proper ventilation, condensation can build up behind walls and ceilings. Over time, that can lead to:
- Mould growth
- Timber rot
- Internal damage
- Health concerns
We have inspected homes less than five years old where poorly managed condensation caused major issues behind plasterboard. Once moisture gets trapped inside a structure, repairs become expensive very quickly.
Roof Ventilation and Wall Cavities Are Now Essential
Under NCC 2026, ventilation requirements become much stricter.
This includes:
- Roof cavity ventilation
- Exhaust fans vented externally
- Ventilated wall cavities behind cladding systems
For townhouse builds, these details affect:
- Roof design
- Façade thickness
- Material selection
- Construction sequencing
Good builders already pay close attention to these areas. The difference now is that the code leaves far less room for shortcuts.
So, How Much More Will a Townhouse Cost Under NCC 2026?
Cost Increases Depend on the Site and Design
Industry estimates vary widely.
| Source | Estimated Cost Increase |
| Master Builders Queensland | Around $30,000 |
| AGWA | Around $4,300 |
| Broader Industry Estimates | 10%–15% increase |
The final number depends on:
- Site slope
- Orientation
- Design efficiency
- Window sizing
- Material selections
- Builder experience
A poorly designed townhouse can become very expensive under the new rules. A well-planned project often absorbs the changes far more efficiently.
Cheap Designs Often Cost More Later
One mistake we see regularly is owners chasing the cheapest early-stage design fee possible.
Unfortunately, poorly resolved designs usually create:
- Redesign costs
- Assessment failures
- Delayed permits
- Material upgrades late in documentation
That is where budgets can blow out.
Good planning might not feel exciting at the start, but it saves headaches once construction begins.
How Smart Planning Can Reduce NCC 2026 Cost Pressures
Bring Energy Consultants Into the Project Early
Leaving NatHERS assessments until the documentation phase is asking for trouble.
Early energy modelling helps identify:
- Better window placement
- Orientation improvements
- Passive heating opportunities
- Shading strategies
Simple layout adjustments during concept design can avoid expensive glazing or insulation upgrades later.
Ask Builders Direct Questions Before Signing Contracts
Before committing to a townhouse build, ask:
- Does the quote fully include NCC 2026 compliance?
- Are accessibility upgrades included?
- Has the energy assessment been completed?
- Is the contract fixed price?
- Are ventilation systems fully documented?
The last thing any developer wants is discovering hidden upgrade costs halfway through construction.
Experienced Builders Will Become More Valuable
These changes increase the importance of experienced project coordination.
Townhouse developments now require tighter collaboration between:
- Designers
- Energy assessors
- Building surveyors
- Engineers
- Trades
- Builders
At MJS Construction Group, we are already adjusting our workflows around these upcoming standards because the industry is moving quickly. Builders who prepare early will deliver smoother outcomes for clients.
The NCC 2026 changes will increase construction costs across Melbourne townhouse developments. There is no sugar-coating that reality.
But there is also value behind the investment.
Better insulation, stronger energy performance, improved accessibility, and healthier ventilation standards create homes that are more comfortable, more durable, and cheaper to operate over time.
The biggest risk is not necessarily the higher standards themselves. It is entering a project without understanding how these changes affect the design, approvals, and construction budget from the beginning.
The developers who plan early, engage experienced consultants, and work with builders who understand the new requirements will put themselves in a far stronger position once the new code arrives.
