South Australia's consumer watchdog has urged people in South Australia to avoid dealing with an unlicensed builder based in the Two Wells area, offering tiling and bathroom renovations.

Acting Commissioner for Consumer Affairs Fraser Stroud said Consumer and Business Services had received a number of complaints involving Justin Norman, trading as 'Norman Tiling'.

"We've had complaints from 4 consumers from across Adelaide and Murray Bridge, complaining that this individual has been paid for services that he's failed to deliver in a reasonable time," he said.

"CBS received reports that the work performed by Mr Norman was of a very poor standard, leaving consumers out of pocket while also having to pay a significant amount to rectify the work that had been done.

"This man is also alleged to have been trading while not holding a valid licence."

Mr Stroud said a public warning had now been issued, warning against doing business with Mr Norman.

"I would also encourage anyone who is concerned about their dealings with this individual to contact CBS as soon as possible," he said.

To report a concern about a trader, contact CBS on 131 882.