Recommended repairs to the Northminster car park were not carried out by Peterborough City Council, according to a report commissioned by the authority.
The multi-storey next to the city market is to be demolished after structural engineers said it had reached the end of its life.
The car park has been closed to vehicles since July 26 due to fears vibrations from cars could cause lumps of concrete to fall from the structure.
The council last week released two reports which recommended that the car park should be dismantled, one of which was by the Rolton Group.
In a revealing statement, the firm wrote: “From our inspections of the car park it is evident that the regimes of repair, monitoring and maintenance as recommended in the earlier reports were not implemented.”
Reports, and remedial works, are both said to have ended in 2011, the company added.
The council revealed last week on its website that it had commissioned an internal review to “allow it to better understand the maintenance and monitoring regime in recent years”.
This was in relation to the revelation about repairs not being made, although this was not made clear in the authority’s statement.
Asked for further clarification, a council spokeswoman said the review will be focused specifically on Northminster and will be carried out internally.
No time frame has been given for the review.
The second commissioned report was published by Skanska, a partner of the council which is currently carrying out repairs at Rhubarb Bridge.
A surface level car park will replace the Northminster multi-storey, but long term the area has been earmarked for redevelopment.
Asked if there are other structures in the city where recommended repairs have not taken place, a council spokeswoman said: “Our records show that other buildings in the council’s ownership currently comply with our landlord obligation to be fit for purpose.”