But that was a claim refuted by the department's Acting Executive Director of Building Operations Elizabeth Stewart.

An investigator appointed by the Building Commission assessed the four-storey Central Park apartments in Station Street - where residents have already moved in.

The investigator found a raft of defects, including uncontrolled cracking of the concrete slabs in the basement and ground floors and leaking ceilings in apartments.

There was also persistent "excessive" mould growth on the wall in one apartment's dining room and moss growing on the balcony of another apartment among a long list of defects.

The Building Commission has now issued a Building Rectification Order requiring the identified defects to be repaired.

When developer Mittagong Central Developments was invited to respond to the list, it claimed the fault lay with the residents.

"Many of the alleged defects contained in the draft order are maintenance items or lack of care by the owners to repair and maintain common property," the rectification order stated.

Acting Executive Director of Building Operations Elizabeth Stewart - who issued the order - disagreed, stating they did not result from any failure of the owners in carrying out maintenance and repairs.

The developer also claimed that the principal certifier issued an occupation certificate, so they "would have been satisfied that the works comprising the building met all relevant requirements as at the completion of the building".

However, Ms Stewart said that indicated a "misunderstanding" of the certifier's role.

"Whether various professionals have designed/built or signed off on those particular building elements associated with serious defects, it is evident to the department that serious defects have been observed and are present," Ms Stewart wrote in the order.

The rectification order lays out the time frame to complete the work, with the longest being eight months.