Masterton Town Hall's auditorium has been declared off-limits after an engineering report found it does not meet required earthquake standards.
And council staff are steeling themselves for the possibility of evacuating their offices, if a second report in July finds the offices wanting as well.
The council issued a notice yesterday at noon saying the hall would be closed with immediate effect following an initial structural survey and report.
A council spokesman said the preliminary results indicate that the reinforced concrete frames which brace the Town Hall in the transverse are at a compliance level of 20-25 per cent New Building Standard (NBS), below the legal requirement of 34 per cent.
"Council staff are in the process of contacting all groups and organisations who have future bookings in the hall and will be helping them to find alternative venues."