Australian builders and tradies smashed by the coronavirus pandemic have warned they are reaching crisis point.

Master Builders Australia wants to fast-track government building projects as well as an increase to the commonwealth-funded First Home Loan Deposit Scheme.

The industry body conducted a survey that found nearly three-quarters of respondents had lost 40 per cent of their business because of the pandemic.

Chief executive Denita Wawn said the viability of some 400,000 businesses and 1.2 million workers was on the line.

“The situation is dangerous,” she said on Friday.

“If urgent action is not taken our industry’s role in the economic recovery will be severely blunted.”

Projects that began before the outbreak were providing some relief but new orders have fallen off a cliff.

Ms Wawn said there was also confusion on building sites about how to work around coronavirus restrictions and safety measures.

She said the government should expand eligibility for the home loan scheme to include anyone wanting to purchase new homes.

State and territory governments should also accelerate the construction of social, defence and transport infrastructure projects.

“Our message to governments, is that we understand the enormity of the challenge they face but that these stimulus measures cannot wait,” Ms Wawn said.