How to achieve an eight-star energy efficiency rating and reap the benefits

The higher the energy efficiency rating on a home, the less the power bill.

It’s simple maths, really.

The standard many new homes strive to achieve is six, however, Light House Architecture & Science director and lead scientist, Jenny Edwards says an eight-star energy efficiency rating is easier than people may think.

“Eight stars is actually simple to achieve in our climate because it is so sunny. Even though it is cold in winter we still get that lovely sunshine,” she says.

Light House designs and renovates homes across Canberra, with a focus on sustainability through fusing architecture and science to achieve a higher-than-average EER on their projects.

“The main things we do to achieve an eight-star rating is orienting the house right – point it north in order to soak up that free warmth over winter, but ensuring the house is well-shaded over summer,” Jenny says.

“It should be insulated really well and the building envelope should be relatively air-tight.

“Windows are also key to the building envelope. We always double-glaze and the size of the windows are also important.

“Just because a wall faces north, doesn’t mean the whole thing should be glass, particularly in our climate, because although the windows will soak up the warmth as soon as the sun disappears you lose all that warmth.”

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Jenny says smaller homes produce better energy efficiency.

“A lot of people don’t realise that EER is based off square metre, which means you can build a 300-square-metre home and although it is eight-star, it means you are using that amount of energy on every square metre,” she says.

“We tend to focus on doing smaller houses, so not only are they eight-star but they use less energy per square metre.”

Six stars is the minimum standard for energy efficiency, but Ms Edwards says an eight-star home performs much better.

“A lot of people don’t realise an eight-star house is predicted to require half as much energy for heating and cooling as that of a six-star,” she says.

Light House clients Margaret and John Cook have experienced first-hand the benefits of lower energy costs in their architecturally designed home.

The couple moved to Canberra from Bathurst in 2013 to be close to family and were after a home that was “small, smart and energy efficient”.

“We weren’t intending to build when we first moved to Canberra but we were unsuccessful in looking for a home that met our criteria,” Margaret says.

Margaret and John’s home has an EER of 7.9. The decision to put up side fences that encroached on the afternoon sun meant they fell just short of the eight-star mark.

Their home in Forde was completed in December 2014, after a six-month design process followed by a six-month build.

Margaret says since living in the home, the couple have saved a lot on energy costs.

“Over the last 12 months we have used 33 per cent less than the average two-person home, but if we were a young couple and at work all day it would be even less again,” she says.

John says since living in the home, he’s noticed the difference and benefits of having a high EER.

“There’s usually about 18 degrees difference between inside and outside when we get up in the morning,” he says.

“It was 13 degrees inside the house this morning when it was minus five outside.”

A recent study from the University of Melbourne found home buyers are prepared to pay more for homes with a high EER.

Ms Edwards says two homes she has designed in Franklin and Curtin had an eight-star rating, and both sold for more than 16 per cent above the market value.

“People have begun to realise energy costs have gone up, and people are putting more value on higher EERs,” she says.

7 Keira Street, Narrabundah 

EER: 8 

3 bed/ 2 bed/ 2 bath 

Agent: One Agency Peta Swarbrick Properties, Peta Swarbrick, 0432 391 755

Auction: June 29, 5pm 

Ruby, Gungahlin 

EER: 8 

Agent: POD Projects Group, Marcus Allesch, 0424 409 873