Sydney has fallen behind Melbourne in the push to convert city structures into sustainable green buildings, according to experts.
Figures from the Green Building Council of Australia show Brisbane has the most green-star certified office space in the country followed by Adelaide, Melbourne, Perth, Canberra and then Sydney.
NSW also lags behind on total numbers of certified green star-rated projects either in the planning stage or completed, a category in which Victoria leads.
The difference between the states was partly attributable to more local and state government incentives in Victoria and more building in Melbourne's CBD.
But Sydney was likely to make up the deficit fast, said the Green Building Council of Australia chief operating officer Robin Mellon.
In the past decade Sydney's CBD has added 667,077 square metres of new or refurbished commercial buildings of which 91 per cent had a green star rating.
"As we see huge areas like Barangaroo South being developed, we are going to see that square meterage catching up very fast," Mr Mellon said.
The construction of a four or five-star green building should be cost-neutral, he said.
At the end of the 2011-12 financial year, 20 per cent of Australia's CBD office space was green star-certified, up from 18 per cent in 2010-11, the council's figures show.
Victoria has 176 green star-rated projects, NSW 137 and Queensland 131 of a total of nearly 600 nationally.
Melbourne's Docklands has the highest concentration of green star-rated buildings in Australia.
Council House 2 and Albert Road's Szencorp building were among the city's earliest sustainable architecture.
Melbourne council's push to enshrine green principles in its planning scheme last April would also help, said Jones Lang Lasalle's national director of sustainability Joel Quintal said.
"It's going to require developers to be quite active in their energy efficiency savings," he said.
For a long time the industry had concentrated on green commercial buildings but the focus was now changing to retail, education and other sectors, he said.
Government-sponsored services such as CitySwitch for commercial office tenants and Smart Blocks, for apartment buildings, were having an impact, Mr Mellon said.
GREEN STAR RATED