While we’re all struggling to achieve the industry standard of 6-stars in our new build or home renovation, a new 9-star trend is gaining momentum.

And it seems most of you are keen to get on board too.

After such an overwhelming response to `New home proves nine stars is achievable’ article last month, we decided to take a look at what actually makes a home worthy of a 9-star status.

What does this mean in terms of energy efficiency?

According to Renew Economy, a 9-star house uses 80% less energy to heat and cool than a 6 star house (the current standard), and only 1/10 of the energy of average existing housing stock.

This means that if you include LED’s or CFL for your lighting and are careful with your appliance selection it is possible to have a house that uses very little power. If you then include a grid interactive photovoltaic system, there’s potential to produce more power than you use.

The Melbourne-based Penola House was one of the first to achieve 9.1 stars in 2011.  Built by Positive Footprints, the energy efficient home took out the MBAV Excellence in Housing Best Sustinable Energy Home 2012 Award and it’s easy to see why.

According to their website, the house boasts a very comprehensive environmental specification list, including polished eco-concrete slab, bagged recycled reverse brick veneer walls to bring mass into the upper floor, and high performance double glazed timber windows.

Rainwater harvesting with internal re-use and grey water collection with sub-surface distribution to the now drought-proof garden, complete the package. It also uses a grid interactive photovoltaic system, which ensured their first ever bill was $700 in credit! Amazing. Read more about the Penola House on their website; positivefootprints.com.au

Meanwhile in Perth, Josh Byrne of ABC’s Josh’s House, has proven 10-stars is achievable, and affordable.

Tired of hearing that sustainable construction had to cost more, Josh set about proving that resource efficient homes could be built at comparable cost and time frames to regular houses. Read more about his 10-star home at joshshouse.com.au

But our resident sustainability expert, Danielle King of Green Moves Australia says `9 stars is sadly nowhere near the norm in Australia yet’.  She told Build Online that its much easier to get 9 stars in Western Australia, while builders elsewhere are still getting used to 6 and some 7 star.

1.            First it was 6-star, now 9-star is quickly becoming the new norm – have you noticed this? What happened to 7 and 8?

No, sadly 9 star is not the norm yet, most builders are still focused on achieving 6 star (and some 7 star) performance levels.  Achieving star ratings in each state differ as well.  For example it’s a bit easier to achieve 9 stars in WA and QLD than it is in Victoria due to the variations in climate and requirements to achieve it.

2.            Why do you think achieving 9-stars is so desirable?Danielle_King_head

For me, achieving 9 stars is highly desirable as I’d love a home that works with nature to keep me comfortable and costs significantly less to run.  Why would you pay thousands of dollars a year (and I know of many households that do just that), when you can live for a few hundred dollars (or even utility bill free) by simply designing and building well?  I’d rather spend the money on holidays.

3.            What makes up a 9-star home? And why wasn’t it fully achievable before now?

In Victoria it’s a combination of things ranging from optimal orientation of the home, appropriate glazing in the right place, good use of the right materials (eg taking advantage of thermal mass and solar access), good insulation and so on.   I think it’s always been achievable.

But its been difficult to justify the additional cost of build, and not many have had the knowledge and the attention to detail required to achieve it.  With utility bills on a massive upward trend, anyone who is not considering ongoing running costs in a home they are building, should think again.

4.            It is affordable?

Absolutely.  We have an 8 star home on our ‘Home to Build’ listing that costs just $195,000 and a 9 star home that is costed at $350,000 to build.  When you factor in running costs the extra build cost (and its usually only between 1% and 4% of overall build cost) the owners would be ahead within 2 years.

building-green-homesSo what does it mean to be rated a 9-star or 10 star energy rated house?

According to the NatHERS scale – the federal government-administrated Nationwide House Energy Rating Scheme was introduced to assess the potential thermal comfort of Australian homes on a scale of zero to 10 stars – occupants of houses rated at or around the 10-star mark are unlikely to need much, if any artificial cooling or heating.

At the other end of the scale, a zero-rated house means the building shell does practically nothing to reduce the discomfort of hot or cold weather.

Houses built in 1990 averaged about 1 star on the NatHERS scale. Before the introduction of national energy efficiency regulations for houses in 2003, less than one per cent of Australian houses achieved 5 stars.

Many well designed houses are now being built above 6 stars or more, and examples are available on the Your Home website at: yourhome.gov.au

Read more at the NatHERS website; nathers.gov.au

The good news is, rating your home’s green star performance is about to get a whole lot easier.

In what’s set to be a game changer for the industry, the Green Building Council of Australia (GBCA) recently launched the Green Star Performance rating tool, aimed at improving the efficiency and environmental sustainability of Australia’s existing buildings.

According to Architecture & Design, the Green Star Performance rating tool will enable building owners and managers to identify pathways to improve the environmental and financial sustainability of their assets over time.

Read more about the rating tool at architectureanddesign.com.au

What do you think? Are 9-stars quickly becoming the new norm?

Are you building a green home? We’d love to hear from you.

Email our editor direct; sacha.strebe@informa.com