NatHERS Assessments & Certificates
NatHERS accredited assessors providing NCC-compliant assessments & NatHERS certificates across Australia
If you need a NatHERS assessment or certificate for building approval, Green Choice Consulting provides compliant energy efficiency assessments for new homes, renovations, alterations and multi-dwelling residential developments across Australia.
Our NatHERS accredited assessors prepare accurate, NCC-compliant NatHERS certificates to support council approvals, BASIX requirements (NSW) and 7-star energy efficiency compliance under NCC 2022.
Whether you are working with an architect, builder or certifier, we assess your design using approved NatHERS software and provide clear advice to help your project meet energy efficiency requirements efficiently and cost-effectively.
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What Is a NatHERS Assessment?
The Nationwide House Energy Rating Scheme (NatHERS) is Australia’s framework for assessing the thermal performance of residential buildings. A NatHERS assessment evaluates how a home’s design performs in its local climate zone, focusing on the energy required to heat and cool the dwelling to maintain comfortable indoor conditions.
NatHERS assessments apply to:
- New residential dwellings
- Renovations, alterations and extensions
- Multi-dwelling and apartment developments
The outcome of a NatHERS assessment is an energy rating and, where required, a NatHERS certificate that can be used to demonstrate compliance with the National Construction Code.
What Is a NatHERS Certificate?
A NatHERS certificate is the formal document issued after a NatHERS assessment has been completed by an accredited assessor.
It confirms that a dwelling has been assessed using approved NatHERS software and shows whether the design meets the required energy efficiency targets.
NatHERS certificates are commonly required for:
- Development applications and construction certificates
- NCC energy efficiency compliance
- BASIX thermal comfort compliance (NSW)
- Building approvals for Class 1, Class 2 and Class 4 residential buildings
When Is a NatHERS Certificate Required?
To get a building permit you must demonstrate that your home meets the minimum energy efficiency requirements outlined in the National Construction Code. The most common pathway used in Australia is a NatHERS assessment showing that your home achieves a 7-star energy rating.
NatHERS reports can be used to show compliance for:
- Class 1: Single dwellings, including detached houses and townhouses
- Class 2: Apartment buildings, typically multi-unit residential buildings
- Class 4: Dwellings within non-residential buildings
While the compliance pathway can vary by state and project type, NatHERS remains the most widely used method for demonstrating residential thermal performance across Australia.
Work With NatHERS Accredited Assessors
Only NatHERS accredited assessors are authorised to prepare NatHERS assessments and issue certificates using approved NatHERS software.
All NatHERS assessors must:
- Hold accreditation with an Assessor Accrediting Organisation (AAO)
- Maintain ongoing professional development
- Be subject to quality audits to ensure assessment accuracy
Engaging an accredited assessor early can help identify design inefficiencies, reduce the risk of redesign, and avoid unnecessary construction costs later in the project.
At Green Choice Consulting, our assessors have extensive experience across residential and multi-dwelling developments and provide practical, compliance-focused advice throughout the design and approval process.
- Accredited – Our Director Albert Burton holds accreditation with Design Matters National and undertakes on-going professional development.
- Accurate & Reliable – We are subjected to random Quality Audits to ensure a high standard of service.
- Endorsed Energy Reports – Only an accredited NatHERS assessor can complete an energy assessment using NatHERS software. Some areas and developments may not accept reports from non-accredited assessors.
- Proven Cost Savings – We can identify design constraints and provide solutions which will lower your building costs.
What’s Involved in a NatHERS Assessment?
NatHERS assessments are completed using licensed thermal modelling software. The assessor inputs detailed information about the proposed dwelling, including construction type, materials, glazing and insulation, and the software simulates how the home will perform under typical occupancy conditions, and usage of heating and cooling systems.
Based on this information, the software is able to deliver a star rating that reflects the level of energy efficiency of the dwelling. Specific heating and cooling targets are set by NatHERS, which the dwelling must meet to achieve the minimum 7-star rating.
To accurately model a dwelling, we generally require:
- A site plan showing boundaries and house position
- Floor plans showing room layout
- Elevations showing walls, roof and window locations
- Electrical plans showing lighting, exhaust fans and ceiling fans
- Section drawings (if available)
The modelling process estimates the heating and cooling energy required to maintain comfort and generates a star rating based on performance targets set for the relevant climate zone.
If some information is unavailable, we’re happy to discuss alternative assessment options.
NatHERS Star Ratings Explained
NatHERS uses a 10-star rating system to indicate how energy-efficient a home’s design is, based on its thermal performance. A higher star rating means less energy is required to heat and cool the home.
Historically, a 6-star rating was the minimum standard for most residential buildings. Under NCC 2022, this has increased to a 7-star minimum for new homes in most states and territories, subject to local adoption timelines.
For a detailed explanation of how star ratings work and what they mean for your project, see our guide to NatHERS star ratings.
How to achieve a NatHERS 7-star rating
In order to achieve a 7-star rating, certain key considerations need to be made in the dwelling’s design phase to ensure optimum energy efficiency. These considerations include:
- Orientation and direction in which the home faces
- Insulation
- Building materials used
- Various design features, e.g. double glazed windows
An Australian Government department, Your Home, has provided free Design For Place home designs to help home builders create energy-efficient, sustainable homes to suit various climates and lifestyles.
This can help you with design choices and assist you in discussions with your architect or builder.
NatHERS Energy Ratings - Enquire Now
Does your project require a NatHERS Certificate? Green Choice Consulting can help ensure your project is compliant with the National Construction Code with our range of energy efficiency reports. Speak with an accredited assessor today about your NatHERS assessment.
Updates to the Nationwide House Energy Rating Scheme
NatHERS Whole Of Home
In addition to the minimum 7-star rating requirement, the Nationwide House Energy Rating Scheme (NatHERS) now includes a Whole of Home Performance Rating.
This assessment measures the overall energy efficiency of a home, considering the energy use of fixed appliances such as:
- Lighting
- Heating and cooling systems
- Hot water
- Renewable energy sources like solar panels and battery storage.
Previously, these elements were excluded from NatHERS ratings since they could be upgraded over time. However, the Whole of Home rating provides a more comprehensive snapshot of a home’s energy consumption, greenhouse gas emissions, and potential energy costs.
This rating is separate from the traditional star rating and is scored out of 100, helping homeowners, builders, and designers make informed decisions about energy-efficient improvements.
NatHERS Existing Homes
NatHERS is set to expand in mid-2025 to include energy assessments for existing homes, providing homeowners with a structured approach to enhance their property’s energy efficiency and comfort.
Previously focused on new constructions, this initiative aims to address the energy performance of older homes, many of which were built before the enforcement of current energy efficiency standards. Notably, approximately 70% of Australia’s 11 million homes have an energy rating of 3 stars or less, highlighting a significant opportunity for improvement.
A NatHERS assessment for existing homes will be conducted by trained and accredited assessors who will evaluate two primary components:
- Thermal Performance
- Whole of Home Energy Performance
By participating in this expanded NatHERS assessment, homeowners can gain valuable insights into their property’s energy efficiency, identify areas for improvement, and implement upgrades that can lead to reduced energy consumption, lower utility bills, and a smaller carbon footprint.
NatHERS Certificate Cost
The starting price for a NatHERS Certificate on a class 1 dwelling is $200 (plus GST).
The price varies depending on the size, complexity and requirements of the project. We find most projects fall within the price range below:
Single Storey Dwellings: $200-$300 + GST
Double Storey Dwellings: $300-$500 + GST
We’re happy to provide a tailored quote based on your plans and approval requirements.
BASIX vs NatHERS
In New South Wales only, BASIX is used to demonstrate compliance with water, thermal comfort and energy targets. NatHERS assessments are commonly used as the thermal comfort pathway within BASIX, using detailed thermal modelling rather than simplified prescriptive methods.
When conducting a BASIX assessment, there are 2 options within the thermal comfort section:
- Do-It-Yourself (D.I.Y) Method: This is a simple assessment method that uses standard construction materials and methods. It does not require the house to be modelled, which means the compliance requirements will be higher in most cases.
- NatHERS Simulation method: This method involves doing a detailed assessment of the house by modelling its design in NatHERS software. This method provides the expected energy usage for heating and cooling based on the design of the house, it’s materials and the climate.
BASIX does not require a 7 star rating to be achieved in NatHERS software, however it does allow the use of NatHERS software to demonstrate compliance with the thermal comfort section for separate heating and cooling loads.
The thermal comfort section sets separate heating and cooling target loads, which must be met to show that your project is compliant. A NatHERS certificate will show the separate heating and cooling loads, and will verify that the required BASIX loads have been met.
To understand how the two schemes differ and when each applies, read our article on the key differences between BASIX and NatHERS.
Get Your NatHERS Certificate
If you need a NatHERS assessment or certificate for your project, our accredited assessors are ready to assist.
Get in touch today to discuss your plans and ensure your project meets energy efficiency compliance requirements with confidence.
Frequently Asked Questions
What is NatHERS?
The Nationwide House Energy Rating Scheme (NatHERS) provides energy ratings for new dwellings, renovations, alterations and extensions. The goal is to create more energy efficient homes helping you to save money on your energy bills.
NatHERS provides a star rating from 1 to 10 based on the home’s design, construction materials, insulation, glazing and climate zone.
What is a NatHERS Certificate and Star Rating?
New developments with multiple dwellings in Australia must meet minimum energy efficiency requirements, as set by the National Construction Code. NatHERS, or the Nationwide House Energy Rating Scheme, is the means by which new residential properties are scored on their energy efficiency.
Using a 10-star rating system, residential properties must achieve a minimum 7-star rating following a thermal assessment, in order to achieve compliance.
What does the NatHERS Star Rating Mean?
A NatHERS rating is given on a scale from 1-10, with 10 being considered a passive house, that does not require the use of any artificial heating or cooling systems. A higher rating indicates that less energy is required to keep the house at a comfortable temperature.
A 0 star rated dwelling would offer no insulation from the external weather and would require almost constant heating or cooling to stay comfortable.
NatHERS Star Rating Calculator - How is the Rating Calculated?
An accredited assessor will input information into NatHERS software (FirstRate5) and using thermal modelling the software will determine how much energy is used for heating and cooling your home.
Based on your climate zone NatHERS sets out specific heating and cooling targets which must be met for your project to achieve the 7-star energy rating standard.
What are the benefits of getting a NatHERS Assessment?
When we prepare a report following a NatHERS assessment, we will provide you with information so that you know how much energy your home is using for heating and cooling. If your home does not achieve a 7-star rating, we will provide you with options to reduce the energy usage of your home and meet the minimum NatHERS energy rating. This will help improve the value of your property and reduce your energy consumption, making your home more energy efficient.
How do NatHERS climate zones affect my energy rating?
NatHERS assessments are based on Australia’s distinct climate zones, each with its own heating and cooling performance targets. A home design that performs well in one climate zone may achieve a different star rating in another due to variations in temperature, humidity and seasonal conditions. Your local climate zone plays a key role in determining insulation requirements, glazing performance and overall thermal efficiency.
Do I need a new NatHERS assessment if my plans change?
In many cases, yes. Changes to building plans such as window sizes, glazing type, insulation levels, materials, floor layout or building orientation can affect a dwelling’s thermal performance. If changes occur after an assessment has been completed, the NatHERS model may need to be updated to ensure the final design remains compliant with NCC energy efficiency requirements.
When should I organise a NatHERS assessment during my project?
A NatHERS assessment is best completed during the early design stage, before plans are finalised. Early assessments allow energy efficiency improvements to be incorporated into the design efficiently, reducing the risk of costly redesigns during development approval or construction. However, assessments can still be completed at later stages if required.
Do renovations and extensions require a NatHERS assessment?
Renovations, alterations and extensions may require a NatHERS assessment depending on the size and scope of the works and local approval requirements. Larger extensions or projects that significantly change a home’s thermal envelope are more likely to require assessment to demonstrate compliance with current energy efficiency standards.
How does NatHERS apply to apartments and multi-dwelling developments?
For Class 2 residential buildings, NatHERS assessments are used to evaluate the thermal performance of individual dwellings as well as shared building elements. Assessment methods may vary depending on building size, layout and approval pathways, but the goal remains the same, ensuring the development meets NCC energy efficiency requirements.
What NatHERS software do assessors use?
Accredited assessors use approved thermal modelling software such as FirstRate5, AccuRate or HERO. These tools simulate how a dwelling performs in its local climate based on construction materials, insulation, glazing and design features, generating an energy efficiency star rating in line with NatHERS standards.
Is NatHERS the only way to meet NCC energy efficiency requirements?
NatHERS is the most widely used compliance pathway for residential energy efficiency in Australia, but the NCC does allow alternative methods in certain circumstances. Available pathways can vary by state, building type and project scope. NatHERS remains the preferred option for most residential developments due to its accuracy and flexibility.
Can a higher NatHERS rating reduce long-term energy costs?
Homes with higher NatHERS ratings generally require less energy for heating and cooling, which can lead to lower energy bills and improved indoor comfort. While achieving a higher rating may involve upfront design considerations, it often delivers long-term savings, increased comfort and improved property value.
Who can complete a NatHERS Certificate?
An assessor must be trained with an Assessor Accrediting Organisation (AAO) to be able to issue a NatHERS certificate. Currently there are three AAO’s that offer membership for accreditation.
- ABSA: Australia Building Sustainability Association
- DMN: Design Matters National
- HERA: House Energy Raters Association
All assessors must hold a Certificate IV in one of the following courses:
- Certificate IV in Home Energy Efficiency and Sustainability (Thermal Performance Assessment) – CPP41119
- Certificate IV in Home Energy Efficiency and Sustainability (Home Sustainability Assessment and Thermal Performance Assessment) – CPP41119
- Certificate IV in NatHERS Assessment – CPP41212 (no longer available)
All assessors are required to under going audits and must get 12 CPD (Continuing Professional Development) points each year.
Get Expert Support With Your NatHERS Certificate
If you’re planning a new home, renovation or residential development, a correctly prepared NatHERS assessment is essential for achieving NCC compliance and avoiding delays during approval. Working with an accredited assessor ensures your energy rating is accurate, defensible and aligned with current regulatory requirements.
At Green Choice Consulting, we provide Australia-wide NatHERS assessments and certificates, supporting everything from early design advice through to final approvals. Whether you need a 7-star NatHERS certificate, Whole of Home assessment, or guidance on meeting BASIX or NCC energy efficiency requirements, our experienced team is here to help.
Contact us today to discuss your project and obtain a compliant NatHERS certificate with confidence.