The proposal backed today was hailed as a "masterpiece'' by one of its architects, Sir Miles Warren.
Surrounded by empty lots where its once-proud neighbouring buildings have been demolished - deemed too battered by the quakes to survive - the category one listed Christchurch Town Hall stood up in the quakes.
Media were given a guided tour of the 41-year-old building yesterday.
Standing in the entrance foyer, apart from a slight musty smell and ever-so-slightly sloping floor, superficial cracks in the marble tiles and occasional concrete beam, the building withstood the ferocity of the magnitude 6.3 jolt of February 22, 2011 "rather well'', engineers told the media congregation.
The Town Hall has been closed since February 22, 2011 when 185 people died in the city, and its future has been a hot topic ever since.
Some argue that just the main 2500-seat auditorium should be saved, while the smaller 1000-seat James Hay Theatre should go as its acoustics aren't up to scratch for modern music concerts.
But under the backed plan, everything will be rebuilt, including the auditorium, entrance foyer, Limes Room, The Boaters and the Cambridge Room, and acoustics will be upgraded in the James Hay Theatre.
Most of its damage was caused by liquefaction and lateral spreading of the ground towards the Avon River.
Patrick Cantillon, project manager of the proposed rebuild, said the building has dropped by 300mm in some areas and up to 600mm in others.
"It surfed down towards the river,'' he said.
"The building itself is quite robust. It's just the land beneath.''
But cracks in concrete beams can be repaired with "injections'', while the floors can be taken up, braces added to its weaker corners, and the ground below strengthened.
The council voted unanimously to repair the existing building to 100 per cent of the new building standard in November last year.
Sir Miles described the building as the "most important'' he had designed during his illustrious career.
"It's the only building in New Zealand that has an international reputation as a work of architecture in the second half of the 20th century.''
Christchurch city councillors are also expected to vote this afternoon on whether Hagley Oval will host 2015 Cricket World Cup games.
The Environment Court granted the ground resource consent earlier this month.
Councillors will today consider whether to grant a lease to Canterbury Cricket for its proposed embankment, pavilion and retractable lighting towers.
