Great Australian ‘green’ dream can be a reality

The Farrells say their home shows that you don’t have to do something crazy, expensive or unusual to build a comfortable sustainable house, writes Julie Power.

Not far from the Farrell’s simple and conventional twoand-a-half bedroom home north of Sydney, there is a hobbit house – and a cobbit version made of straw bales.

Unusual or not, these three homes share one thing. They all use much less energy than the six-star minimum under the now 12-year-old house energy ratings scheme for new homes in the National Construction Code (NCC).

Even if this is raised to seven stars, an option under consideration by governments, the Farrell’s three-yearold architect-designed home has far surpassed it. The home rated 8.2 stars at a total cost of $450,000. It was a bit more than a conventional build including some ‘‘splurges’’. Tony Farrell says the home was designed to show ‘‘you don’t have to do something crazy, expensive or unusual to build a comfy sustainable house’’.

They didn’t use anything fancy. Working with architect Andy Marlow of Envirotecture and builder Living Green Designer Homes, the couple made small modifications to improve the energy efficiency of conventional building materials. For example, to keep the temperature even inside and reduce the need for cooling or heating, the home was sited due north with a deeper than usual sheltered deck. The eaves over windows are wider than usual, and the windows facing the western sun are smaller. It has a light coloured roof to deflect heat which is covered in solar panels. Again the roof colour was ahead of the curve.

Last year NSW minister Rob Stokes announced plans requiring new homes to have light-coloured roofs, especially in Sydney’s west and south-west suburbs where temperatures can be 10 degrees higher than eastern Sydney.

The townhouse they owned previously at Terrigal with sea views was such a heat sink that Teresa came to dread summers. The comparison between the old and new was ‘‘off the scale’’. ‘‘Guests come in on a hot summer day, and think we have the airconditioning on,’’ Teresa says. ‘‘On a cold winter’s day, guests ask if we have the heating on.’’

Since moving in, they have been net exporters of energy to the grid, even after charging an electric vehicle that they bought as an ‘‘investment in the future of the planet’’.

The Farrells say the pressure on the government to maintain the six-star energy efficiency rating for new homes, and those being substantially changed, called NatHERS is disappointing and shortsighted. Mainstream builders, including those represented by the Master Builders Association, are lobbying for any change to be delayed until 2025, citing costs to industry and homeowners and the need for more research.

But architects, environmental groups, many councils, tenants unions and social welfare groups say the current changes don’t go far enough and want a shift to at least seven stars. In a joint statement, they say delays of even three years would leave hundreds of thousands of households paying more in energy bills and incurring much greater costs to retrofit. They argue the regulatory impact statement prepared for the federal government underestimates the broader costs of less energy-efficient homes on the environment.

David Meiklejohn is the co-ordinator of a coalition of more than 100 councils called Climate Emergency Australia that has declared its commitment to net zero. Despite that, many are yet to vote on whether to support a move to seven stars. Some face opposition from developers who say the changes will add costs – for example, achieving a seven-star plus rating usually requires orienting a home on each block to the north.

Meiklejohn says the climate had changed too much and too quickly in the past 12 years to maintain six stars.

‘‘We are living and seeing the effects of climate change. The floods are the more extreme example, along with the heatwave in Perth and western Sydney... that stuff is speeding up with more and more of these events occurring closer to together,’’ he says. ‘‘What might have been seen like a leisurely pace 12 years ago, you can’t do that with climate change policy now. You need to adjust because the impact is changing and at a faster rate than the strategy.’’

As the climate warmed, Australians would use significantly more energy to keep their homes cool and comfortable.

Meiklejohn says the small lift to seven stars would be a game changer when it comes to Australia’s commitment to achieving net zero emissions by 2050. Buildings use more than half of Australia’s electricity. Operating them generates a quarter of national greenhouse emission, he says.

‘‘Based on future climate projections, over the next 50 years, it will take massive amounts of expensive airconditioning to find some level of comfort to live in a house that has been built to our current building standards,’’ he says.

In 2019 state and federal government energy ministers agreed to a trajectory for lower energy buildings to zero energy for commercial and residential buildings in Australia.

They said bills were too high, there was little incentive to make rented homes energy efficient, and ‘‘the impact of suboptimal buildings built now would last a long time’’. ‘‘Given that we’re estimated to build just over 1 million homes in the next three years, delaying changes to the NCC could add $2 billion to household energy bills and 15 million tonnes of carbon emissions by 2030,’’ says Meiklejohn.

Stronger energy standards for new buildings can reduce energy bills by up to $29 billion; cut energy network costs by up to $12.6 billion and deliver up to 78 million tonnes of cumulative emissions savings, he said.

NatHERS does not apply to appliances inside the house but to how it is built. There are four main areas it covers: the orientation of a home; its insulation; its leakage of air; and thermal mass (the ability of the material to absorb, store and release heat).

As the star ratings increase, a home is more likely to have some of these features, for example, north facing aspect, shading to prevent harsh sun and double or triple glazed windows.

As well as a seven-star increase, another change being considered is the introduction of a whole-of-household energy budget that will take into consideration appliances and solar panels. To heat a square metre in a home in Melbourne takes 155 kw a year in a one-star house, 32kw a year in a sixstar house, 23kw in seven stars, and 1kw in a 10-star house.

Savings vary, depending on the local climate with those living in cold or warm climates benefiting than those living in temperate zones.

Australia is overdue for a change to the NatHERS, says Renew, a non-profit organisation providing advice on energy efficiency.

Since six stars were introduced, Australia’s performance has fallen behind comparable countries, where the energy efficiency of new buildings is typically 40 per cent better than Australia. Renew’s analysis found that a six-star home in eastern Sydney using gas and electricity to cool and heat the home cost $2001 to run a year.

The same home in a much hotter part of Sydney cost $2146. If these homes were to switch to seven star electric with solar, for example, both would see bills plummet – to $546 a year in the east and $584 in Richmond.

The 106 councils that have signed up to Climate Emergency Australia have voted to move all parts of the economy to net zero emissions.

Blacktown, for example, declared a state of climate emergency in 2020. Its temperature is routinely higher than the rest of Sydney, and by 2036 its population will exceed Tasmania’s 541,000. It will then have what is expected to be the largest population of any NSW council, creating demand for new housing in greenfield areas, says a council spokesperson.

Like many ‘‘green’’ councils, it has yet to adopt a position on the proposed increase to seven NatHERS stars, and was studying the full ramifications of the issue. ‘‘Blacktown City Council always places the health and wellbeing of residents as its highest priority,’’ says Mayor Tony Bleasdale.

Sydney City Council is also reviewing the proposed changes to the NatHERS ratings. The City supported a minimum seven-stars on a trajectory to higher ratings, integrated into the NCC.

Lord Mayor Clover Moore says independent national and international reports had confirmed the global climate crisis was worse than feared, and that immediate action is required for our long-term survival. ‘‘Ensuring all buildings are designed to the highest environmental standards, to minimise energy requirements and maximise liveability and comfort, is crucial if we are to tackle climate change in all ways possible.’’ Moore says.

In Victoria, like NSW, demand for greener homes is growing, driven by consumer demand. Rory Costelloe, the executive director of developer Villawood Properties, agrees. His recent developments have included ‘‘seven-star precincts’’ which have been popular with buyers and shows ‘‘it can be done’’. ‘‘They have an ambient temperature of about 18 degrees in winter, 23 in summer, so it doesn’t become a hot or a cold box. That’s a real difference,’’ he says.

However, he says, the industry needs some lead time before the star ratings increase. Many homeowners enter into a forward contract to buy land and find a builder. This can result in an 18-month delay on a large greenfield home development site.

Homes at Brendan Condon’s development The Cape at Cape Paterson – two hours east of Melbourne

– average eight stars for energy efficiency. He says more than 15,000 potential homeowners have signed up for updates.

All homes there have higher ratings than the proposed lift to seven stars. They cost a bit more, but Condon and others claim within three to five years they break even from lower energy costs – plus additional benefits for health and the environment. ‘‘There was outcry from industry when we moved to five stars. You would’ve thought the world was going to an end. But it didn’t. The move to six stars had similar pushback. Now this change to seven stars is overdue,’’ he says.

Condon equates the additional extra upfront costs of having a more energyefficient home to operating a cheap car that you can’t afford to drive. ‘‘If you buy a poorly built home, it requires a huge amount of energy and causes energy poverty. You’ve got to look at the capital and operational costs.’’