NatHERS Star Energy Ratings & Certificates
Building energy ratings that go beyond the minimum
A NatHERS star energy rating and certificate is the most common way to demonstrate your new house design meets the minimum 7-star energy efficiency and Whole of Home requirements of the National Construction Code (NCC) and gain building approval in Australia.
At Zone Zero, we’re passionate about supporting architects, designers and owners in creating comfortable, healthy and energy efficient homes for the future.
As a certified Thermal Performance Assessor (energy rating consultant), Jemma provides accredited NatHERS assessments and certificates that not only satisfy compliance requirements but also leverage her architectural experience to identify opportunities for improved comfort, livability, and long-term running costs. This ensures your project meets, and can exceed, minimum standards, without compromising your design intent.
Our home energy efficiency assessment & report process
When you partner with Zone Zero, you’re choosing a streamlined and collaborative path to compliance and beyond. Our process is designed to deliver accurate energy ratings and efficiency solutions with clarity, ensuring the best outcomes for your project.
1. Alignment & Initial Review
We take the time to understand your project’s specific needs, challenges and goals with an initial consultation. Our energy rating consultant will then review your architectural plans and specifications, allowing us to understand your vision and identify any potential challenges early on.
2. Advanced Thermal Modelling & Analysis
We use accredited software to build a detailed digital model of your house. We input all relevant data to accurately simulate its thermal performance and generate an initial NatHERS energy efficiency rating and Whole of Home score.
4. Final Certification
Once the design achieves the desired rating, we issue the certified and stamped plans and NatHERS Certificate required for your building permit application.
3. Actionable Recommendations
If the design doesn’t yet meet the desired standard, we don’t just identify problems, we provide solutions. Your energy rating consultant will provide a clear set of options, such as upgrading insulation or adjusting window specifications, to help you reach compliance and beyond, without compromising your design intent.
Benefits of an energy efficient house
A comprehensive energy efficiency report from Zone Zero is an investment in the future of your property. The benefits extend far beyond meeting building permit approval, a higher rating home is fundamentally a better home, offering advantages for your comfort, finances, and long-term sustainability.
Save money - lower energy bills through smarter performance.
Reduce environmental impact - minimise your home’s carbon footprint.
Improve comfort - enjoy consistent temperatures and better indoor air quality year-round.
Future-proof your home - higher ratings support long-term sustainability and re-sale value.
Streamlined, expert guidance - Zone Zero provides a collaborate process, practical solutions and accredited ratings that helps homeowners and design professionals achieve compliance, optimise performance, and maintain design intent.
Need a NatHERS certificate for your project?
Zone Zero will guide you through the process and make sure your design gets the best outcome.
FAQs
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A NatHERS rating measures the energy efficiency of a home design. It predicts how much heating and cooling the home will need to stay comfortable year-round, based on hundreds of factors, including its climate, orientation, design, materials, and construction. The rating is scored out of 10 stars — the higher the stars, the more efficient and comfortable the home.
Read more in this Simple Guide on our blog.
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A Whole of Home assessment provides a score (out of 100) that reflects the overall energy performance of a home. While the NatHERS star rating measures the thermal performance of the building itself, the Whole of Home score takes into account the energy use of appliances such as hot water systems, lighting, heating and cooling, cooking, and pool or spa equipment. It also factors in any solar energy generation and battery storage. The minimum rating is 60/100 for new houses and 50/100 for apartments. A score of 100 indicates a net-zero energy home, while scores above 100 are possible for homes that generate more energy than they use.
This assessment is now a mandatory compliance requirement in many states, including Western Australia. At Zone Zero, we provide Whole of Home assessments alongside your NatHERS star rating, ensuring your project meets all current energy efficiency regulations seamlessly. -
A NatHERS certificate is the most common way to demonstrate compliance with the National Construction Code (NCC) of Australia. For new homes, the NCC requires a minimum 7-star energy rating plus Whole of Home compliance. Without a certificate, you won’t be able to gain building approval.
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For the best outcome, it’s ideal to engage a NatHERS energy rating consultant in the design stage. The earlier in the process that a thermal performance assessor becomes involved, the more scope there is to improve the energy efficiency and comfort of the building in simple, low-cost ways.
Zone Zero offers sustainable design consultancy, supporting architects, designers and owners to optimise their projects from the start.
If your design is already finalised and you’re seeking building approval, we can still provide actionable recommendations that enhance performance without causing significant rework.
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Providing the right documents up front ensures a smoother, more accurate assessment. Complete details allow us to avoid conservative default values in the modelling, which can underestimate your home’s performance and lower your rating.
For a NatHERS star rating, you’ll typically need a drawing set (site plan, floor plans, elevations, sections, window/door schedules, and an electrical/lighting plan).
For a Whole of Home score, you’ll also need information on proposed appliances (heating and cooling, hot water, cooking, lighting, pool or spa equipment, and any solar or battery systems).
To make this easier, we’ve created a documentation checklist and template. During the Alignment and Initial Review stage, we’ll help identify any missing details that could improve your rating.
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Most assessments are completed within 5–10 business days, depending on the project size and the information provided. Faster turnarounds can be arranged if needed.
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The cost for a NatHERS rating and certificate varies depending on the size and complexity of the home. Contact us for a tailored quote for your project.
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If your design falls short of minimum compliance requirements, or of your own performance goals, we’ll provide targeted recommendations, whether that’s improving insulation, optimising glazing, adjusting shading, or refining material choices - so your home achieves better comfort and efficiency.
