We Have All The Answers To Your NatHERS Questions!

 

The Nationwide House Energy Rating Scheme (commonly known as NatHERS) was launched in 1993. NatHERS is a sustainability measurement system that rates residential dwellings and apartment buildings on the basis of their energy efficiency and thermal performance. 

NatHERS certificate constitutes a vital component of BASIX. 

The House thermal rating is generated by a NatHERS accredited application tool. The NatHERS assessment is one of the most efficient and affordable approaches to obtaining residential thermal comfort compliance. 

While the NatHERS certificate focuses on residential construction, the NABERS energy rating is essential for commercial spaces such as office buildings, hospitals, educational centres, shopping complexes, retail stores, etc.

What Is NatHERS Rating?

NatHERS assessment utilises a 10-star rating scale to determine the thermal performance of residential dwellings across Australia. 

The National Construction Code (NCC) references these energy and thermal performance star ratings specifying a minimum number of star levels for all new residential structures constructed in Australia.

The Housing Industry Association estimates that approximately 71% of residential projects use star rating as a measuring unit to demonstrate thermal performance and energy efficiency compliance. 

A higher star rating signifies that the dwelling or residential structure is less dependent on artificial or active heating and cooling. The highest star rating in the NatHERS certificate is a 10-star rating. 

• A 0-star house means indicates residential building fabric does nothing to maintain natural comfort levels inside the house. 
• A 6-star NatHERS rating is the minimum level of thermal compliance as per the National Construction Code. 
• A NatHERS 10-star house is a 100% passive house with absolutely no artificial heating and cooling requirement to maintain the house temperature and humidity at comfort levels. 

The star rating system is similar in both NatHERS and NABERS energy ratings, although the scale is different.

Which Building Classes Require NatHERS Certificate?

Any residential project that requires a building permit for construction needs BASIX Certificates and thermal efficiency compliance either through the DIY method or NatHERS assessment. 

NatHERS can be used to demonstrate thermal comfort compliance for all residential projects belonging to the following classes: 

Class 1a structures: detached single residential structure or one of a group of attached dwellings including row house, terrace house, townhouse or villa unit. 

Class 2 buildings: an apartment building or multi-residential structure involving two or more occupancy units. In multi-residential units, the entire building collectively (and not each unit) need to achieve a minimum 6-star rating on the NatHERS certificate to demonstrate compliance. 

Class 4 part of a building: a residential structure inside a non-residential/commercial building.

What Does A NatHERS Certificate Include?

A NatHERS Thermal and energy assessment Certificate will offer insights regarding: 

• Key design components within the building. 
• The construction materials used. 
• Glazing types.

How To Assess NatHERS Star Rating?

NatHERS is assessed performed using a process of thermal modelling. The proposed dwelling is modelled using NatHERS-approved software. 

The type of building, construction material, glazing specifications, artificial lighting and thermal insulation are used to evaluate the overall annual thermal performance of the project. 

There are four steps for generating a NatHERS star rating. These include: 

• Generating a simulation model in a NatHERS accredited software. 
• Determining the temperature and climatic zone of the residential project 
• Determining the requirement for heating and cooling systems 
• Calculating a rating out of 10 (This step may include several iterations to achieve the desired star rating).

Also Read: Best Tips To Achieve 6-star Ratings For NATHERS Certification

What Are The Benefits Of NatHERS Star Ratings?

The NatHERS certification and star rating system present the following benefits: 

• Accurate and measurable results 
• Reduced operational energy expenses 
• Reduced complications of complying with BASIX 
• Improved property value in the market 

Want your residential project to reap the benefits mentioned above? Ensure to hire a qualified team of business consultants to assist your project by offering the necessary expertise to complete not just the NatHERS assessment for residential constriction but NABERS energy rating for commercial projects as well.

Which construction factors can help you achieve a six-star or more NatHERS rating? 

Each residential structure might perform differently depending on its individual climatic and microclimatic zoning, adjacent building structures and shading from neighbouring objects. 

Common building strategies for all climates include: 

Considering the insulation of the building envelope (ceilings and walls). 

• Use appropriate shading and window glazing. 
• Adjust the heat gains from natural sunlight by minimising west and east-facing glazing or using adjustable shading features. 
• Integrate weather sealing on all external windows and doors. 
• Use appropriate openings (windows and doors) for facilitating cross ventilation, passive cooling and natural lighting. 

Conclusion 

It is highly recommended to hire a building consultant at the early stages so that they can work with your design experts and architects to quantify the impact of different design components and construction measures on the overall house heating and cooling performance.