The number of buildings estimated to have suffered significant damage from Monday's 6.3 earthquake in central Christchurch's red zone is now estimated at 147.
It is not known how many of those are buildings that were previously undamaged.
The Canterbury Earthquake Recovery Authority says it will assess them this week, but it is likely more than 100 emergency and urgent demolitions will have to take place.
As well as further damage to Christchurch Cathedral and the the Catholic basilica, the Hotel Grand Chancellor has twisted further.
CERA chief executive Roger Sutton says 20 engineers assessed the CBD on Tuesday and a number of buildings have moved.
Demolitions manager Warwick Isaacs says the latest quakes have probably brought down some buildings already condemned after the February quake.
Meanwhile, people are urged not to enter red-stickered buildings. Mayor Bob Parker says there have been reports some people in hillside suburbs are going back into unsafe homes, despite the serious risk of rockfall.
Mr Parker says they are putting their safety at risk, as well as the safety of those who may have to rescue them.