Mark Desmond Tilbury and Susan Vaughane Tilbury, trading as Mark Tilbury Home Improvements, received the caution after the $136,370 renovation of a Willetton home in 2010.
The Building Services Board heard the renovations were delayed because some defects needed fixing and the project had not made practical completion until April 2012.
Even then, the owner found more faults and defects and submitted a workmanship complaint in February 2014.
The building commissioner ordered the pair to return $2479.32 to the homeowners in August 2015, before the State Administrative Tribunal made them pay another $9928.12 in February.
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READ NOWBuilding commissioner Peter Gow said the case was a reminder to anyone who carried out building works that they could be made to pay for incomplete or unsatisfactory work.
“Builders who fail to maintain proper standards or who act inappropriately may face disciplinary or prosecution action…which can result in a caution or fines,” he said.
“The Building Commission will continue to hold to account and name those who put the public interest and the reputation of the building industry at risk.”