A report into Hamilton's Founders Theatre has confirmed the facility is an earthquake risk and will have to be strengthened if it is to reopen.
The 54-year-old theatre was abruptly closed at the beginning of March due to health and safety concerns.
A detailed seismic assessment has found the most critical areas of weakness are the roof over the auditorium and the stage house.
Redeveloping the theatre is estimated to cost about $20 million.
A new one would cost $50 million.