Palmerston North's police station is undergoing earthquake strengthening and refurbishment work expected to take about a year to complete.
The station, which opened in late 2005, was one of several city buildings designed by Kevin O'Connor and Associates found to have potential deficiencies.
The Church Street building was constructed in the early 1970s, before additions were made ahead of its opening as a police station.
The connection between the older and newer structures is the station's weakness, affecting its seismic performance.
RNZ asked police if they had made efforts to pursue Kevin O'Connor and Associates or other parties for costs to do with the strengthening.
"Police do not wish to comment at this stage," police said in a statement.
After a lengthy investigation, Engineering New Zealand recently fined Kevin O'Connor $3500, ordered it to pay $35,000 in costs, but did not suspend or remove him as a chartered engineer.
Engineering NZ's disciplinary committee looked at six buildings' designs and found O'Connor was negligent but not incompetent.
The addition to the older structure was given consent by the Palmerston North City Council and met standards of the time.
Police said the upgrade work was slated to finish in December 2022. The project's cost was "commercially sensitive with the main contractor and police".
Last year, police said they had received a draft report detailing the station's seismic shortfalls.
When asked if they had since had a fuller report, and what the shortfalls were, police said: "The station is being upgraded throughout, is being made fit for purpose and a modern working environment created. The structural strengthening scheme is included."
The statement said the station would remain open throughout the works.
Its public front counter had temporarily moved to the police central district headquarters next door.
Police had also recently made improvements to the Feilding station and the Highbury community station in Palmerston North, where staff could work from.
At the station's opening, then-police minister Annette King said it cost about $9 million to upgrade and extend the building formerly occupied by Central Power.
Police moved across the road from their former building, which opened in 1939.