In the past three months the council dealt with three cases of non-compliant building work; three cases would be "more normal'' for a period of a year, rather than three months.
"Ideally, you don't want to have any, but I don't think anybody has got a perfect record in this area,'' Mr Mabon said yesterday.
"But when you get three in three months, when you normally get that over the course of a year, it does raise eyebrows quite a bit,'' Mr Mabon said.
Addressing a report to the council's customer services committee last week, Mr Mabon said he understood that an incorrect assumption had been made by the builders that the work was exempt, yet it had been "immediately obvious to our building officer that it was not exempt work''.
Yesterday, he said he could not confirm that in all three cases council building officers had become aware of the non-compliance and decided to investigate, but he believed that was the case for at least two of the three cases. Complaints could also give rise to investigations.
The council has the ability to issue an infringement notice with a maximum fine of $200,000.
The value of two of the three projects was $30,000 and $150,000 respectively. No figure was available for the third project.
By July 8 this year, the council had approved 533 consents.
