The council is also working through the contents of a written engineering report, which elaborates on the initial verbal advice that led to the March 4 decision to close the theatre building. The council is planning to have its engineering advice peer reviewed by mid-May before deciding what to do about fixing the historic building.
Mr Yule said while the situation had got worse since the March 4 closure of the theatre building, the council was committed to reopening the Opera House, although indications were that this would likely become a long and costly project.
"I expect it could well cost several million to get these buildings up to code but we just don't have any idea at the moment," he said.
"There's no risk that these buildings are somehow going to be lost; they're incredibly important to our community. We need to just carefully work through the options as to how we get them strengthened."
Opera House staff would continue to work in the Municipal Building for now although the council was "working through whether they can stay or not," Mr Yule said.
Opera House chief executive Christine Spring said the facility's staff "will continue to be employed while we await further peer review work on the engineering reports".
Yesterday's closure of the Municipal Building meant a number of events due to be held at its venues would have to be relocated.
The affected venues include the complex's Assembly Hall and Shakespeare Room.
Tonight's performance of Bill Haley Jr and The Comets, scheduled for the Assembly Hall, has been relocated to the Lowe Family Performing Arts Centre at Lindisfarne College, Hastings.
Ticketing agent Ticketek was yesterday contacting ticket holders for the event. The council said current tickets would be honoured at the new venue and queries or requests for refunds should be directed to Ticketek on 0800 4TICKETS.
Miss Spring said other facilities within the Opera House complex - Opera Kitchen, Ticketek, Dish and Hawke's Bay Winegrowers' offices - were not affected by the closure of the Municipal Building.
The council said it was "continuing to work through the implications" of the closure with Hutchinsons Furnishers, a tenant of the building. Hutchinsons management had indicated they would continue to operate from their current location.
Mr Yule said on March 4 he was "very surprised" to learn of the earthquake vulnerabilities the facility was facing because strengthening work had been a core part of a $13.6 million upgrade of the complex carried out between 2004 and 2007.
