Northampton Guildhall is a soft target that is at risk from terrorists.
That is the conclusion of a report that recommends further security measures at Northampton Borough Council's headquarters, in the form of magnetically locked glass door.
If approved, the door would prevent free access to the council chamber the Great Hall and all other rooms in the public building.
The report, by architects Roger Coy, said a review by anti-terrorism advisor Howard Lytwynchuk had found the building to be "porous and at risk".
Roger Coy said: "The need for enhanced security and controlled access followed national security and terrorism incidents and warnings to the council that soft targets such as Northampton Guildhall could be at risk.
"Therefore, it was considered by the council that there was an essential and urgent need to upgrade the security measures in respect of the personal safety and working environment of local authority personnel, including elected council members."
Aside from giving added protection for councilors and council staff, the report mentions the need for secure premises when preparing ballot boxes for local and national elections.
The new glass door would replace the large timber sliding door that is set back in the entrance hall. It blocks off the corridor leading to the Great Hall, when closed.
The report says the wooden door provides poor security because staff have to open it to see who is trying to gain entry.
Simply locking the the main front door at the top of the Guildhall steps has been discounted as Roger Coy said this would give the message to members of the public that 'vistors are not welcome'.
They added that certain events such as weddings and civic events need the main doors to be open, meaning security guards would need to be on duty to provide the extra security needed.
The report said: "For private events that use multiple rooms within the Guildhall, events where alcohol is on sale, and for public events, the council hires security staff to control access to the Guildhall.
"This method of managed / controlled access works for such events, but it is cost prohibitive to use 24hours a day throughout the year."