How much extra does a 7-star home cost in Australia?

Published 15 July 2026

Published estimates range from $710 for a Queensland Class 1 dwelling in Australian Building Codes Board modelling, expressed in 2021 dollars, to $3,310 for a single-storey, four-bedroom Victorian house in a government worked example. The Housing Industry Association (HIA) produced a much higher adjusted estimate of $13,257 per dwelling under Option A, but the figures use different methods and are not directly comparable.

NCC 2022 lifted the model thermal-performance requirement for new homes from 6 stars to the equivalent of 7 stars and introduced a separate Whole of Home energy-use budget. States and territories adopted the changes at different times and with local variations.

There is no official national average cost premium. Industry and consumer groups also disagree on whether the added cost is outweighed by lower energy bills and other benefits. NCC 2025 introduced no further residential energy-efficiency changes, while most additional residential code changes are paused until mid-2029.

Reported premium range: $710–$3,310; Official estimates; Official government estimates. The residential building industry's own submission put a house far higher, at $13,257
Annual bill savings reported: $183–$300; Official range; Official range across jurisdictions; independent modelling of all-electric homes reports savings above $1,000
7-star minimum: Introduced in NCC 2022; Official · NCC 2025; First adopted from October 2023; NCC 2025 made no further residential energy changes
States and territories at 7 stars: 6 of 8; Compiled from official sources · 2026; Tasmania and the Northern Territory have not adopted the 7-star minimum for new houses

Why Australia's 7-star energy standard has divided the building industryAustralia's National Construction Code lifted the minimum energy rating for new houses from six stars to seven under NCC 2022, the first increase in more than a decade. States and territories then rol…

What does a NatHERS energy rating measure?The Nationwide House Energy Rating Scheme (NatHERS) measures the thermal performance of a home's design, not its total energy use.

Section 01 · Standard

What does the 7-star home energy standard require?

The NCC 2022 residential energy provisions generally require two separate performance outcomes: thermal performance equivalent to 7 NatHERS stars and compliance with a Whole of Home annual energy-use budget. The 7-star rating measures the building shell, while Whole of Home is a separate score.

Under the NCC 2022 NatHERS pathway, houses generally require a Whole of Home score of at least 60 out of 100, while apartments generally require at least 50. Alternative compliance pathways, state and territory variations and local concessions may apply.

Features commonly identified in government guidance include:

north-facing living areas
reduced east and west-facing glass
shading, low-e or tinted glazing
roof and wall insulation
lighter-coloured roofs and walls
ceiling fans

Victorian guidance identifies better design and orientation, improved insulation and higher-performance glazing as common differences between 6-star and 7-star homes.

There is no single fixed package. The thermal performance outcome depends on factors including climate, orientation, building design, insulation and glazing. The separate Whole of Home score is affected by heating and cooling, hot water, lighting, cooking, plug-in appliances, pool and spa equipment, rooftop solar and battery storage.

Victorian Government guidance states that considering design and orientation early can reduce the need for additional materials or construction changes.

What the NCC 2022 residential energy requirements measure
Requirement	What it covers	Example features
Thermal performance rating	The predicted energy needed to heat and cool the home, based on its building shell, local climate and design.	Orientation, insulation, glazing, shading, roof colour
Whole of Home rating	Predicted annual energy use from major appliances and equipment, less energy generated on site. Houses generally require a score of at least 60, while apartments generally require at least 50.	Heating and cooling, hot water, lighting, cooking, plug-in appliances, and pool and spa equipment
On-site generation and storage	Solar generation and battery storage included in the Whole of Home assessment.	Rooftop solar and batteries

Source · NatHERS, Introducing Whole of Home ratings, 23 March 2023; Queensland Government residential energy-efficiency standards; Victorian Government 7-star energy-efficiency building standards.

Section 02 · Cost

How much more does a 7-star home cost than a 6-star home?

Reported premiums for the 7-star uplift range from $710 to $13,257 per dwelling, with the highest estimate almost 19 times the lowest. Three estimates exist, each using a different method, home design and location, and none of them represents a single national figure.

Queensland results, ABCB regulatory modelling: $710–$764; Class 1 houses $710, Class 2 units $764.; Present-value cost-benefit analysis for the NCC 2019-to-2022 transition, not a builder quote.
Victoria, household example: $3,310; Estimated extra materials cost for a single-storey four-bedroom house to meet the 7-star standard.
HIA, industry estimate: $13,257; HIA estimated $13,257 per dwelling under Option A and $9,093 per dwelling under Option B.

Australian Building Codes Board, NCC 2022 Residential Energy Efficiency: Final Decision RIS, July 2022; Victorian Government household guidance; HIA submission to the Consultation RIS, 2021. The ABCB figures are expressed in 2021 dollars.

A separate, earlier Queensland Government study modelling the state's move from its own QDC 4.1 standard up to the national NCC2019 6-star benchmark, not the 7-star standard discussed above, illustrates how much design, climate zone and orientation can affect upgrade costs:

an earlier Queensland uplift study found a two-storey house design cost more to upgrade as the climate zone number increased, $3,998 in zone 2 rising to $7,745 in zone 5, while an older-style Queenslander design moved the opposite way, $12,040 in zone 2 falling to $9,286 in zone 5
orientation alone moved the estimated cost by nearly $8,000 for the same design in the same climate zone, from $2,188 facing north to $10,135 facing west
glazing was the largest single cost driver in three of the four Queensland house designs tested, well ahead of insulation
more than 58% of affected dwellings in that earlier study showed an absolute reduction in construction cost, even with no change to the dwelling design, so cost is not automatically higher under a tighter standard

Section 03 · States

How 7-star home requirements differ by state and territory

Six of Australia's eight states and territories have adopted 7-star-based requirements, with implementation dates spanning 19 months from October 2023 to May 2025. Tasmania and the Northern Territory have not adopted the 7-star minimum, while several adopting jurisdictions apply local variations, exclusions or concessions.

ACT · First to fully implement

7-star adopted in full

Adopted: 15 January 2024
Status: full NCC 2022 energy and Whole of Home compliance

Victoria

Mandatory from 1 May 2024

Straight 6-to-7-star uplift plus Whole of Home budget
Household cost example: $3,310

Queensland

Commenced 1 May 2024

Houses need 7 stars plus a Whole of Home score of 60 or more
Units need 50; apartment buildings average 7 with no unit below 6

New South Wales

BASIX increases from 1 October 2023

Thermal target lifted from average 5.5–6 stars to 7
Excludes climate zones 9, 10, 11 and apartments up to 5 storeys

South Australia

7 stars from 1 October 2024

Concessions allow some Class 1 homes to use 6-star thermal performance
Must still meet NCC 2022 energy usage and condensation rules

Western Australia

Transition ended 30 April 2025

From 1 May 2025, permits must nominate NCC 2022 or its first amendment
Transitional provisions were extended twice before this deadline took effect

Tasmania

NCC 2022 restored, until 1 May 2027

Building Amendment Act 2026 received Royal Assent 5 June 2026
New homes comply under NCC 2022 until NCC 2025 is adopted from 1 May 2027, but Tasmania's own state variation keeps residential energy efficiency at 6 stars (BCA 2019 Amendment 1), not the national 7-star standard

Northern Territory

Has not adopted NCC 2022 energy rules

Minimum ratings remain 5 stars for houses
3.5 stars for apartments

Source: ACT, Victorian, Queensland, NSW, South Australian, Western Australian, Tasmanian and Northern Territory government guidance, 2023 to July 2026.

State and national milestones, 2023 to 2029

Nine milestones trace the implementation of the 7-star-based requirements from October 2023 and the pause on most further residential changes until mid-2029.

1 October 2023
NSW lifts its BASIX thermal target
The BASIX thermal performance target rises from an average of 5.5–6 stars to 7, with exclusions for some climate zones and smaller apartment buildings.
15 January 2024
ACT fully implements the new standard
The ACT becomes the first jurisdiction to fully adopt NCC 2022's energy efficiency provisions.
1 May 2024
Victoria and Queensland make the standard mandatory
Both states require 7 stars and a Whole of Home budget for new homes from this date.
1 October 2024
South Australia moves to 7 stars, with concessions
Some Class 1 homes can still use 6-star thermal performance while meeting the energy usage and condensation rules.
1 May 2025
WA's transition period ends
New permit applications must nominate NCC 2022 or its first amendment from this date.
22 October 2025
Building ministers agree the pause
Building Ministers confirm that no further residential changes will be made until mid-2029, except for essential quality and safety measures, and decide the content and timing of NCC 2025.
April 2026
Treasury reports on the code, Tasmania moves to freeze the code
Treasury releases its interim report on the broader NCC Modernisation Project. Separately, Tasmania's government moves to legislate a freeze on adopting the national code, opposed by the state Labor opposition.
1 May 2026
NCC 2025 becomes available for adoption
States and territories can adopt NCC 2025 from this date. It makes no change to the 7-star and Whole of Home residential energy requirements introduced under NCC 2022.
Late 2026 and mid-2029
Final report due, with most residential changes paused
The NCC Modernisation Project's final report is due in late 2026. Most further residential changes are paused until mid-2029, except for essential safety and quality measures.

Sources: Australian Treasury, Building Ministers' Meeting communiqué, 22 October 2025; NCC Modernisation Project interim report, April 2026; Tasmanian Government, May 2026.

Section 04 · Payback

How long does it take for a 7-star home to repay the extra cost?

The simple payback period is about 11 years in the Victorian Government's worked example. There is no official national payback figure, and the result depends on the upfront cost, annual energy savings and financing assumptions.

Section 05

Victoria's 7-star cost and savings example

The Victorian model compares a one-off additional materials cost with estimated annual mortgage repayments and predicted energy bill savings.

Step 1

Extra build cost, $3,310 one-off

Step 2

Extra loan cost, about $150 a year on a 30-year mortgage

Step 3

Bill savings, at least $300 a year

Step 4

Modelled net saving, at least $150 a year under the source's assumptions

Source: Victorian Government household guidance, updated 2026, citing NCC analysis conducted in 2021.

Section 06 · Savings

How much can a 7-star home save on energy bills?

Published estimates of energy bill savings vary because they measure different combinations of thermal performance, appliances and rooftop solar. Selected government estimates for houses range from about $183 to at least $300 a year, while broader independent modelling reports savings above $1,000 a year.

Government · minimum compliance: $183–$300 a year; Official; DCCEEW reports $183 nationally, Treasury and Queensland about $185, and Victoria at least $300.
NSW (higher standard) and independent modelling: More than $1,000 a year; Higher scope, not guaranteed; Current NSW guidance says an average home meeting the higher BASIX standards could save more than $1,000 a year.
Single national average: Not published; No single figure is treated as the authoritative national estimate.; The Commonwealth, states and independent modellers each publish a different number for a different scope.

DCCEEW; Treasury; Queensland and Victorian government guidance; NSW Government; Renew, 2021.

The differences between the government and Renew estimates mainly reflect their scope. The government figures describe selected minimum-compliance or regulatory examples, while Renew's modelling includes efficient appliances and rooftop solar. Differences in energy prices, dwelling design and modelling assumptions may also affect the results.

These savings are being reported against real bill pressure. In the 12 months to May 2026, the Australian Bureau of Statistics recorded electricity prices up 21.1%, or 3.9% excluding Commonwealth and state rebates, while new dwelling prices rose 5.6%, driven mainly by project home builders passing through higher labour and materials costs.

Section 07 · Debate

Why builders and consumer groups disagree about 7-star home costs

The 2021 Consultation Regulation Impact Statement estimated national net costs of $2.366 billion under one scenario and $1.795 billion under another. HIA's adjusted modelling estimated higher net costs of $12.894 billion and $8.160 billion, while Renew modelled annual household savings above $1,000 for a broader package that included efficient appliances and rooftop solar. These figures measure different outcomes and are not directly comparable.

Housing Industry Association

OPPOSED THE STANDARD

Argued the standard's costs would outweigh its benefits nationally, and put the per-dwelling cost well above the government's own figures. HIA cited the Consultation Regulation Impact Statement’s finding that costs would exceed benefits by three to one under one scenario and four to one under the other, producing estimated net losses of $2.366 billion and $1.795 billion. After applying its own adjustments to the costs and benefits, HIA estimated net costs of $12.894 billion under Option A and $8.160 billion under Option B. It argued that improving existing housing stock would deliver larger energy savings for less cost than tightening standards for new homes only.

Source: HIA submission to the Consultation RIS, 2021.

Master Builders Queensland

OPPOSED THE STANDARD

Said the government's own modelling showed the change would cost more than it saved in Queensland, and called for a delay. Master Builders Queensland cited government modelling showing a net cost of around $201.9 million a year in the state, and said some builders were reporting price increases of about $20,000 a house when applying the new requirements. It called for the change to be delayed to NCC 2025 rather than commencing under NCC 2022.

Source: Master Builders Queensland, 2022.

Renew

SUPPORTED THE STANDARD

Modelled savings well above the government's own figures and argued households would be better off from day one. Renew's “Households better off” report modelled a 7-star home with efficient appliances and solar across four cities, finding savings high enough that the extra mortgage cost would be offset immediately rather than over a decade. It argued that higher standards benefited households, comfort and emissions alike, rather than imposing a net cost.

Source: Renew, “Households better off”, 2021.

ClimateWorks Australia and ASBEC

SUPPORTED THE STANDARD

Warned that delaying the standard would cost households money and add to emissions. Research by ClimateWorks Australia and the Australian Sustainable Built Environment Council estimated that delaying the changes by three years would add about $2 billion to household energy bills across the roughly 1.1 million homes expected to be built between 2022 and 2025, as well as adding to emissions from those homes over their lifetime.

Source: ClimateWorks Australia and ASBEC, cited via Renew, 2021.

Where the debate sits now

The broader, separate NCC Modernisation Project received 213 submissions. The review found broad agreement on problems including complexity, cost and inconsistent compliance, but disagreement over the solutions. Its final report is due in late 2026, while most further residential NCC changes are paused until mid-2029, except for essential safety and quality measures.

What supporters argue:

in nearly all Renew scenarios, bill savings exceeded the increase in monthly mortgage repayments
delaying the standard would have cost households collectively, on ClimateWorks and ASBEC's estimate
supporters cite potential comfort and health benefits alongside bill savings

What opponents argue:

the government's own cost-benefit modelling shows a marginal or negative net benefit for some dwelling types, such as Queensland's Class 2 units
retrofitting existing housing stock could deliver larger energy savings for less cost than tightening standards for new homes alone
compliance cost and complexity have grown across the National Construction Code more broadly, not just in energy provisions

Source: Home Energy Rating (NatHERS) household guidance; Victorian Government household guidance.

What the data does and does not show

There is no single national 7-star cost premium. Selected government estimates range from $710 in ABCB modelling for Queensland to $3,310 in a Victorian worked example, while HIA estimated $13,257 under its own assumptions. The figures use different methods and are not directly comparable. Selected government estimates for houses report annual bill savings of about $185 to at least $300. Broader NSW BASIX guidance and independent modelling that includes efficient appliances and rooftop solar report savings above $1,000 a year.

Official data does not include:

a measured national average cost premium
a national payback figure
official cost estimates for every state and territory
a like-for-like breakdown by climate zone, orientation or home size
a multi-year cost-premium trend

Section 08

Frequently asked questions

How much extra does a 7-star home cost in Australia?

There is no single national figure. Australian Building Codes Board regulatory modelling put the Queensland cost at $710 for a Class 1 house and $764 for a Class 2 unit, in 2021 dollars. Victoria's own worked example puts the extra materials cost at $3,310 for a single-storey four-bedroom house. HIA's industry submission estimated $13,257 per dwelling under Option A and $9,093 under Option B. The figures use different methods and are not directly comparable.

How much can a 7-star home save on energy bills each year?

DCCEEW reports about $183 in national bill savings for new homes; Treasury and Queensland report around $185 for houses; Victoria reports at least $300 a year. Independent modelling by Renew of all-electric homes with efficient appliances and rooftop solar reports savings of $1,056 in Melbourne, $1,203 in Sydney, $1,231 in Hobart and $1,357 in Perth. NSW guidance says homes meeting the higher BASIX standards could save more than $1,000 a year.

How long does it take to pay back the 7-star cost premium?

Victoria's worked example gives a simple payback of about 11 years, based on $3,310 extra upfront cost against at least $300 a year in savings, before financing or discounting. On the Victorian mortgage comparison, extra materials add about $150 a year to a 30-year mortgage, producing a modelled net saving of at least $150 a year. There is no official national payback figure.

Which states have adopted the 7-star standard?

Six of eight jurisdictions have adopted 7-star-based requirements. NSW's BASIX changes took effect 1 October 2023, ACT on 15 January 2024, Victoria and Queensland on 1 May 2024, South Australia on 1 October 2024 (with concessions), and Western Australia from 1 May 2025 after a transition. Tasmania and the Northern Territory have not adopted the 7-star minimum for new houses.

References

Australian Building Codes Board – NCC 2022 Residential Energy Efficiency: Final Decision RIS, July 2022 · abcb.gov.au
Queensland Government / SPR – Aligning Queensland's Energy Efficiency Requirements for Residential Dwellings with National Standards: Cost-Benefit Analysis, March 2023 · hpw.qld.gov.au
Queensland Government – Residential energy efficiency standards, updated July 2025 · housing.qld.gov.au
DCCEEW – Residential buildings, updated February 2026 · dcceew.gov.au
Australian Treasury – NCC Modernisation Project: Interim Report, April 2026 · treasury.gov.au
Australian Treasury – Building Ministers' Meeting communiqué, October 2025 · treasury.gov.au
Victorian Government – 7-star building standards: Common questions, updated 2026 · energy.vic.gov.au
NSW Planning Portal – Increase to BASIX Standards, October 2023 · planningportal.nsw.gov.au
PlanSA – New building standards, from October 2024 · plan.sa.gov.au
WA Government – Building Focus Issue 12: Implementing NCC 2022 in WA, July 2025 · wa.gov.au
Northern Territory Government – Energy efficiency of residential buildings · nt.gov.au
Tasmanian Government – Energy efficiency for new homes · cbos.tas.gov.au
Tasmanian Legislation – Building Amendment Act 2026, June 2026 · legislation.tas.gov.au
NatHERS – Introducing Whole of Home ratings, March 2023 · nathers.gov.au
ABS – Consumer Price Index, Australia, May 2026 · Australian Bureau of Statistics
Housing Industry Association – Residential building energy-efficiency proposal: Consultation RIS submission, November 2021 · hia.com.au