A warning from the Office of Consumer and Business affairs said Maurice Robinson, formerly of Adelaide's northern suburbs, has never held a building work contractor's license but has continued to enter into contracts to install or organise installation of carports and verandahs.

Mr Robinson is prohibited from being employed or otherwise engaged in the business of a building work contractor or consultant, an order made by the District Court, June 23 this year said.

"The court has also disqualified him from being licensed or registered under the Building Work Contractors Act 1995 until further order," a spokesperson from the office said.

She said the 58-year-old had been convicted in the Elizabeth Magistrates Court of 12 counts of breaching the Building Work Contractors Act 1995 and was fined $18,000.

"Last February, Mr Robinson was subsequently found guilty of contempt of court for this offence and given a 10-day jail term which was suspended and a media release was issued to alert the public of his misdemeanours," she said.

Investigations by the office have found that Mr Robinson had provided false license details and forged council approvals to customers, as well as constructed "substandard" carports and verandas which have left consumers with the extra expense and inconvenience of fixing the jobs.

He is also known by the office for taking deposits for work that he never completed and falsely offered rainwater tank supply and installation.

"Last December he was also publicly named by the Consumer Affairs Minister Jennifer Rankine over a rainwater tank supply and installation scam," the spokesperson said.