PricewaterhouseCoopers has urged the Australian Public Service to lead the country by building flexible workplaces and overcoming biases that prevent older people from winning jobs and promotions.

The firm says that means trusting public servants to do their jobs out of the office in the hours they choose, and even allowing them to work for multiple employers.

However, its new report, 1-2 skip a few 99-100, suggests the APS has far to go: it highlights its ongoing poor performance across several work measures.

The report says the days of the "54/11" public servant – who has a generous, defined-benefit, superannuation pension and retires just before their 55th birthday – are ending, and staff will need to work longer to fund a retirement to the age of 100.

Yet while the APS has older staff than most employers, it lacks what ageing workers desire: "jobs that allow for far greater flexibility and autonomy than the average job today allows".

Federal public servants are less likely than other Australians to have part-time jobs.

Very few work from home, even occasionally: only one in 10 did so in 2013, when telework data was last reported, compared with one in four workers across all industries.

The PwC report cited recent research findings that staff "who worked from home at least once a week were 48 per cent more likely to rate their job a 10 [out of 10] on the happiness scale".

Canberra-based PwC partner Nick Myburgh said flexible workplaces required smarter ways of managing staff.

"There's a very traditional view here [in government] of 'unless the employee is sitting at the desk where I can see them, they're obviously goofing off'," he said on Thursday. "That mindset has got to change."

Mr Myburgh said the challenge was to change the bureaucracy's rigid approaches to managing people so as to keep staff happy, productive and wanting to stay.

"If someone can work from home – or even work for a number of different employers at the same time – we should be trying do that ..." he said.

"We've now got tremendous ability to hook up via video conferences and Google hangouts. If you're a sceptical manager, you could still call them up, right?"

Public service leaders have warned for years that departments must adapt to employees' changing preferences.

In 2013, then Department of the Prime Minister and Cabinet head Ian Watt said managers needed to regard flexible work practices as "a positive part of our workplaces rather than a grudging concession".

"No position or level should be deemed off limits to someone interested in flexible working arrangements," Dr Watt said.

In 2012, then prime minister Julia Gillard set a target of increasing the share of APS staff who teleworked at least once a week from 4 per cent to 12 per cent by 2020.

However, the government scrapped the national telework website last year and stopped reporting on the APS' progress two years ago.