But when it comes to washing his clothes, he has no such modern conveniences, usually having to line up at a local men's hostel or spend up to $50 of his pension at a laundromat.

"If you're not (at the hostel) early, you miss out," the 55-year-old said. "The other alternative is the laundromat but it costs a lot. I fill those stripey bags and it's between $40 or $50."

A free mobile laundry for Sydney's homeless to be launched on Friday will meet this most basic need, with the 21-year-old co-founders saying it will provide dignity and respect as well as clean clothes.

Childhood friends Lucas Patchett and Nicholas Marchesi came up with the idea last year, fitting out an old van nicknamed Sudsy with a generator, water tanks and two large washing machines and dryers, taking to the streets in their home town of Brisbane.

"We wanted to improve the hygiene standards of the homeless so we came up with this crazy idea of building a free mobile laundry," Mr Marchesi said.

"We bought two washing machines and two dryers and put them in the back of a van and started driving around parks and drop in centres and washing and drying clothes for free."

Since then, the Orange Sky Laundry service has spread to Victoria and now NSW, with $100,000 in funding from the state government and The Good Guys.

The vans cost about $70,000 to fit out and another $10,000 a year to run, with the laundry being done by volunteers who will work alongside other homelessness services such as food vans.

Mr Marchesi, a business development manager, said the reaction from the homeless community has been overwhelming.

"People are surprised, they are really blown away," he said.

"Our friends on the street may have been done over once before and we have their most valuable possessions. We really feel privileged to chuck their clothes in our washing machines.

"It takes about an hour to wash and dry their possessions but that hour is a really awesome opportunity to have a conversation."

According to figures from the City of Sydney, there are more than 350 rough sleepers in the city, and many more staying in crisis accommodation.

Pete de Graaf, 53, has spent the past six years living out of a swag after losing his job as a kitchen hand. He became one of Orange Sky Laundry's first customers, handing over a small shopping bag of dirty clothes.

"It's been about a week since I last did some laundry," he said. "I've almost run out of clean clothes so I'm kind of glad. Clean clothes are really important when you've got things to do."

Mr Marchesi and Mr Patchett got the name for their service from the musician Alexi Murdoch's Orange Sky, which is a song about lending a hand to those in need.

"The first thing we all do in the morning is put a fresh set of clean clothes on," Mr Patchett said.

"Everyone's made of the same stuff. We think everyone should have that same basic human right."