The Green (Star) building revolution? Not so fast!

A five star (NABERS) rated building in an Australian central business district.

In 2003, the Green Building Council of Australia (GBCA) introduced Green Star, a tool that rates the environmental performance of buildings. Green Star is highly comparable with LEED in the United States (Leadership in Energy and Environmental Design), and BREEAM in the United Kingdom (Building Research Establishment Environmental Assessment Methodology).

The GBCA boasts about the revolution it has started. Currently more than 7 million square meters of Australia’s built up space is labelled as having high levels of environmental performance, which includes 18% of all office space in the central business districts (CBD) of major cities.

A Green Star revolution in Australia?

Green Star was launched in 2003 by the GBCA, an organisation predominantly run by the Australian construction industry. They wanted to showcase the environmental credentials of the buildings they built. Building on a famous example from the USA the GBCA introduced a building assessment tool.

The idea underlying such tools is simple and elegant: by assessing the environmental performance of a building (in terms of, for instance, energy, water and material use) it can easily be compared to that of other buildings.

It is this ease in making comparisons that makes these assessment tools so attractive. For developers, investors, property owners and occupants alike, it is easy to understand that, on a scale from poor performing to high performing, say one to six stars, a six star building is somehow better than a one star building. Building assessment performs an excellent marketing, branding and displaying function – locally, nationally and internationally.

The numbers the GBCA presents about Green Star’s “successes” are impressive, but what do they actually mean? When put in perspective they show a different image.

Perspective 1: Green Star development follows CDB office development

Green Star is predominantly applied for labelling office space in the CBDs of Australia. Let me therefore first focus on this sector.

Australia currently holds close to 24 million square metres of office space. Although the exact data on the growth of this market is difficult to find, it is estimated that in the years 2006-2009 over 4 million square metres of office space has been added to the market. Taking a more moderate growth rate of only 2% for the other years, then it is safe to say that since 2003 about 8 million square meter of office space has been added to the Australian office market.

The current ratio CBD office space/non-CBD office space is about 3:2. If it is, conservatively, considered that over the last 10 years this ratio has not changed then it follows that about 5.3 million square metres of office space was added to the CBDs of Australia’s major cities since Green Star was introduced in 2003.

The GBCA claims that of all of Australia’s current CBD office space about 2.9 million square metres is now Green Star labelled. Close to half of all CBD office space developed since 2003. That may be considered a very successful outcome.

That having been said, it also implies that for every square metre of Green Star labelled space at least another square metre of non-Green Star labelled space was developed. If Australian office space growth rates turn out to be larger than the conservative 2% I have used here it would imply that the market take-up of a tool as “successful” as Green Star is out of sync with the normal development rate of Australian cities.

Perspective 2: A levelling out of growth

Whilst the numbers that the GBCA presents are impressive, it should be kept in mind that these are accumulated numbers. If they are unpacked as yearly “successes” the picture presented by the GBCA changes a little more. Figure 1 provides an insight.

Green Star data figure

The above figure indicates that whilst the accumulated number of labelled buildings has steadily grown, particularly since 2008, the number of future buildings that will be built as Green Star labelled have leveled out. Between 2009 and 2013 yearly not more than 100 to 150 future buildings were registered with Green Star, whilst in the same years not more than 80 to 130 Green Star buildings (that were earlier registered) were built.

This is not all surprising. With the introduction of a tool such as Green Star it is to be expected that many early adopters try it out in the first years when they can be pioneers and be rewarded as such. It is much harder to get the later adopters on board.

The leveling out of uptake of Green Star at 18% saturation of the office market is not an all too hopeful development. The trick for the GBCA now is to get the majority and laggards on board.

Perspective 3: Green Star is out of sync with everything that is non-CBD office space

There are now close to 9 million residential dwellings in Australia. The average floor area of Australian dwelling has since the mid-1980s steadily been rising from about 150 square meters to close to 220 square meters by the end 2009. Because the majority of Australia’s current residential building stock has been built since the mid-1980s, it is safe to estimate that Australia’s residential building stock is about 1.5 billion square metres.

Not only does this residential stock fully overshadow Australia’s commercial building stock, it also highlights the marginal impact of Green Star. If the CBD “success” of 2.9 million square metres of Green Star labelled space is taken out of its total “success” then another 4.1 million square metres remain. It logically follows from the information provided by the GBCA that this “success” has been achieved in non-CBD areas. In the 1.5 billion square metres of residential space, the 8 million square metres of Australia’s non-CBD space, and all other square meters of built up space that I could not get data on.

4.1 million square metres is about 0.27% of 1.5 billion square meters (about a quartre of a per cent). In other words, outside of the CBDs of Australia’s major cities Green Star has over the course of ten year achieved next to nothing. It is hopeful to see that the GBCA is trying to move into these markets, but it is likely that building labelling will be less popular in these markets.

Perspective 4: Green Star labelled buildings further unpacked

A final issue is the question: How is this “success” of 8 million square metres actually labelled? This is not a trivial question.

Green Star awards three levels of labels: 4 stars (indicating ‘Best Practice’, or meeting 49 to 59% of Green Star’s criteria), 5 stars (indicating ‘Australian Excellence’, or meeting 60 to 74 % of the criteria), or 6 stars (indicating ‘World Leadership’, or meeting more than 75% of the criteria).

Green Star does not give insight into how many buildings or square metres fit each category, but some counterfactuals may help here: Green Star’s counterpart in the Unites States, LEED (Leadership in Energy and Environmental Design), and its (partly mandatory) Australian counterpart, NABERS (National Australian Built Environment Rating System). These tools respectively see only 6% and 8% of their buildings in their highest labelling category.

Given that Green Star 6 star buildings receive much media attention on the GBCA’s website it appears that awarding the highest possible rating still is a unique occasion for the GBCA. This gives at least food for thought. If, say, less than 10% of the labels are actually awarded for ‘World Leadership’ then what is truly revolutionary about the 90% of other labels awarded?

In conclusion: What makes for a revolution?

Green Star has received accolades and critique alike. My take on the tool is that it should be lauded for at least how many people in the Australian building sector know it, and talk about it. In my interviews with Australian policymakers and practitioners Green Star was almost always referred to in one way or the other. But has it caused the revolution in the Australian building sector that the GBCA claims?

It depends, of course, on the definition of ‘revolution’.  In 2007 Apple introduced the iPhone, which clearly started a revolution in communication. By now more than half of all Australians own a smartphone. Four years earlier, the GBCA introduced Green Star. By now less that 0.5% of all built up space in Australia is Green Star labelled. I leave it to you to consider how revolutionary Green Star is.

Post script

An edited version of this blog has appeared on The Conversation, 19 March 2014. 

In a future blog I will carry out a similar exercise for the impact of LEED on the built up space in the United States. My first calculations are not hopeful. I truly hope that I have made an error of at least a factor one hundred (which holds for this evaluation of Green Star as well), but I fear I have not.  If you think I have, please let me know.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Blog at

Up ↑

%d bloggers like this: