Last Updated on January 9, 2024 by Umer Malik
The higher the energy rating, the more you can save on energy bills! Sounds simple, right?
With more and more Australians trying to build more environmentally sustainable homes, it’s recommended to have your house assessed and graded against the NatHERS (Nationwide House Energy Rating Scheme).
While previously the standard for most Australian homes was a 6-star rating, the 2022 National Construction Code (NCC) requires residential buildings to meet at least an energy efficiency of 7 stars under NatHERS.
Now, how can you get a 7-star rating for your NatHERS? Building for a 7-star NatHERS rating doesn’t need to be expensive or complicated. If you are looking for simple ways to make your home energy efficient and achieve a 7-star NatHERS rating, this guide is for you.
Table of Contents
What is NatHERS?
NatHERS, the short form for the Nationwide House Energy Rating Scheme, gives Australian homes and apartments a star rating out of 10 depending on their energy efficiency.
Some features that could affect your NatHERS star rating include layout, design features, insulation, building materials, orientation, and aspect.
A home’s energy rating typically reflects how well the building can use and store energy for heating and cooling. Incorporating smart design choices and energy-efficient features in your house can help improve your NatHERS score and potential for financial savings.
How to Build for 7 Stars NatHERS Rating?
Following discussed are the simple design features and material choices that can improve Australian homes’ energy efficiency and, thus, the 7-star NatHERS rating outcome:
Orientation is the key
The home’s orientation is the foundation for a 7-star NatHERS energy rating. Simply put, you can point your house to the north to catch the radiant heat in winter to enjoy free warming, and in summer, your home will be shaded, resulting in low-cost cooling.
When your home is oriented efficiently alongside complementing with other energy efficiency features, you can significantly lower the need for auxiliary heating and cooling. Correctly positioning your home will allow you to use the power of nature to make your movement easier.
Eliminate gas as an energy source
Once, gas was viewed as the ‘cleaner’ alternative to coal-friendly electricity and an efficient means to sustainability. However, gas is no longer an environmentally friendly or cheap energy source.
So, Australian homes wanting to achieve the gold standard for energy efficiency and sustainability must eliminate gas. Switching to renewable power might seem daunting, but innovations in the energy solutions sector have made it easier to eliminate gas.
For instance, homeowners can include rainwater tanks, energy-efficient LED lighting, battery storage systems, solar PV power, and other energy-efficient appliances to achieve a 7-star NatHERS rating.
Utilize passive cooling strategies
While it’s easy to turn the AC unit when living in Australia’s warmer regions, your house can use multiple simple strategies to enjoy passive cooling.
For instance, builders can design the home’s windows on the opposite sides of the property as a straightforward way to encourage natural ventilation.
Moreover, you can add appropriate insulation at the roofing to save around 40% on cooling bills. Another passive cooling strategy is to add effective shading to block approximately 90% of the summer heat and reduce cooling costs.
Get the NatHERS assessor involved early
Homeowners should consider getting a NatHERS assessor involved early in their home design process.
These assessors are extensively trained to perform the NatHERS Assessment. In addition, they can guide homeowners on different strategies and options to get to a 7-star rating and beyond.
Improve the glazing
In recent years, double and triple glazing costs have significantly reduced. In addition, homeowners can choose from thousands of glazing options.
A professional NatHERS assessor recommends both default and custom window options.
On the one hand, opting for default windows will result in a lower rating, and on the other hand, switching to the custom window where all specifications are known will allow for greater flexibility.
Window sizing, placement, and shading are other vital considerations to improve a home’s energy efficiency.
Builders can more accurately apply mechanical heating and cooling estimates in NatHERS by including more internal doors in the home design.
Places ideal for installing doors might be at the bottom of stairs, at the end of corridors, or to close off occasionally used rooms, like rumpus and media rooms.
Depending on the climate in your area, NatHERS ratings can be improved by increasing the R-value of ceiling, wall, and floor insulation or extending insulation to other areas, like underneath the slab, internal walls, slab edge, the garage, etc. Insulate all necessary areas carefully to prevent condensation risk.
Incorporating sustainable home design principles can help improve your home’s energy efficiency regardless of location. Working with NathHERS accredited assessors during the initial stage of the home design process is vital to building a 7-star rating.
These assessors can provide recommendations to make home energy efficient and provide a valid NatHERS Certificate as evidence. In addition, implementing the above-discussed strategies can help achieve a NatHERS rating as close as 7 stars.