The study also determined that green construction spending currently supports more than 2 million American jobs and generates more than $100 billion in gross domestic product and wages.

The economic impact of the total green construction market from 2000 to 2008, the study found, contributed $178 billion to US gross domestic product; created or saved 2.4 million direct, indirect and induced jobs; and generated $123 billion in wages.

“Our goal is for the phrase ’green building’ to become obsolete, by making all building and retrofits green – and transforming every job in our industry into a green job,” said Rick Fedrizzi, president, CEO and founding chairman of USGBC.

The study, Green buildings create green jobs in a green economy, considered the total value of green buildings and the results include workers from the architects who design them to the construction labourers who pour their foundations to the truck drivers who deliver the materials.

“The study demonstrates that investing in green buildings contributes significantly to our nation’s wealth while creating jobs in a range of occupations, from carpenters to cost estimators,” said Gary Rahl, of Booz Allen Hamilton.

“In many ways, green construction is becoming the standard for development. As a result, it is expected to support nearly 8 million jobs over the next five years, a number four times higher than the previous five years.”

 The union says good use could be made of older workers skills in “recycling and sustainability” and other less physical jobs. The CFMEU campaign was unveiled this week at the union’s national conference.

 Dave Noonan, the national secretary of the union’s construction division, said: “The days of mature-age workers being thrown out like broken toys must end as part of the resolution to tackle the demographic time bomb, but also as a matter of social justice.”

Mr Noonan said many of the jobs once reserved for mature-age building workers, such as gatemen, traffic controllers and hoist drivers, were being taken by labour-hire employees and backpackers. 

“Many mature-age workers could be involved in job planning, training younger workers, ensuring sites are safe, recycling and sustainability,” he said. “What we need is to ensure that a job in construction is a career for life and not one that is terminated as soon as a worker turns 50.”

• Related coverage: ABC News. The Australian. Sydney Morning Herald.