What your home energy score says about your bills


There are countless benefits to having an energy efficient home.

They save you money on heating and cooling costs, the temperature doesn’t fluctuate as much, and they almost always sell for more money on the open market.

How, though, can you tell whether or not your home is energy efficient?

How can you compare your home to the houses in your neighbourhood?

This is where the Nationwide House Energy Rating Scheme comes into play.


The Nationwide House Energy Rating Scheme (NatHERS)

The Nationwide House Energy Rating Scheme (NatHERS) is the official system that determines the home energy score of houses in Australia.

NatHERS rates homes on a scale from 0 to 10, based on how energy efficient they are.

This calculation boils down to how much cooling or heating a home needs to keep the occupants comfortable.

A home that scores a 0 on the NatHERS scale will be a shack with paper-thin walls and no insulation.

It's a place that needs excessive heating and cooling during the cold and warm months.

A 10 on the NatHERS scale is a house that doesn't need any heating and cooling to stay comfortable.

The insulation is 100% effective, keeping the desired temperature the same throughout the year.

As you can tell, it's unlikely that a home will score either a 0 or a 10 on the NatHERS scale.

Almost all homes fall somewhere in the middle.

The NatHERS scale is a fantastic way to find out how energy efficient your home is.

You can also improve the energy efficiency of your home and have it rated again to improve your score.

How are these scores determined?

The backbone of NatHERS score is a software that helps determine how energy efficient your home is.

A NatHERS Accredited Assessor will input multiple data points into the software to generate the score.

Assessors take the following information into consideration when developing your score:

  • The climate and location of your home

  • The size of doors and other openings

  • The size of your rooms

  • The construction of the ceiling, walls, and windows

  • The materials of your home

Assessors don't consider elements like appliances and light fixtures (apart from ceiling fans) during their assessment.

Most homeowners will replace lights and appliances, meaning they aren't worth considering when calculating your home's score.

You can easily replace some lights and appliances to make them more energy efficient.

Reconstructing walls and certain rooms, on the other hand, is a major project.

What Is a typical score?

Energy efficient homes haven't always been a priority.

According to NatHERS, homes that were built in the early 1990s typically receive a one-star score if they haven't been updated.

NatHERS also claims that less than one per cent of Australian homes were granted six stars when the energy efficiency regulations first went into effect in 2003.

Thankfully, energy efficiency has become a priority in recent years.

Houses that have recently been built or have received upgrades will likely surpass the six-star mark into seven stars and beyond.

Those with houses at a score of seven or above should be happy with their results.

This means that they don't rely on artificial heating and cooling to keep their home's temperature within a comfortable range.

Building homes that take advantage of the regional climate is one of the best advancements we've made on our way to energy efficient living.

How to obtain your score

You can get a rating for your home by visiting the NatHERS website and requesting a rating.

There's a quick turnaround on these, and you'll be able to tell your home's energy score without much hassle.

Those who have already obtained a rating can get a new one when they complete major renovations on their home.

These certificates provide you with proof of your home's energy efficiency, which is useful if you're looking to sell.

There are two types of certificates you can receive when you request a rating.

The first is from NatHERS and is a universal, accredited ranking that gives you all of the information you need.

This information includes how much energy you will likely use in a year, the construction of your home, and all of the elements we listed above.

You might have obtained a score from a third-party agency that gives you the same information.

While these can be useful, they don't give you the same score that an accredited NatHERS evaluation will.

The NatHERS scale is universally observed and backed by multiple safeguards, which is why most builders and renovators use NatHERS as the standard.

Building an energy efficient home

Constructing an energy efficient home is something that every modern builder strives for.

In order to create one, though, you have to think about the layout of the home, the materials you will use, and the local climate of the area.

Now that energy efficiency has become the standard in Australia, most new homes will rate above a seven on the NatHERS scale.


This guide is opinion only and should not be taken as financial advice. Check with a financial professional before making any decisions.