Christchurch is still under a state of emergency as the clean-up continues following Saturday's earthquake.
A 7am - 7pm curfew has been in effect.
Mayor Bob Parker says the state of emergency will be reassessed on Tuesday, but at this stage, it remains in place until midday on Wednesday.
Civil Defence was to reduce an inner-city cordon and re-open Cathedral Square and Colombo Street on Tuesday morning.
But it has been forced to revise that after a damaged building on Hereford Street showed further signs of further instability.
The area that remains cordoned off is bounded by Worcester Street, St Asaph Street, Colombo Street and Madras Street.
All of the buildings in the central city have now been inspected with 69% considered safe, 26% have limited access and 55 are deemed unsafe.
Civil Defence says less than 5% of properties in Christchurch are now without water and fewer than 1000 customers are still to have power reconnected.
Bus services will resume on Tuesday morning, except the inner-city shuttle.
Anyone wanting access to the central business district has to go to one of two checkpoints - one on the corner of St Asaph and Colombo Streets, or the other on the corner of Columbo and Gloucester Street.
In terms of road closures, the list is extensive:
Gayhurst Road between Rupert Place and Gloucester Street,
Bealey Ave between Madras and Barbadoes Street,
Colombo Street between Moorhouse Ave and state highway 73,
Latimer Square from Gloucester to Hereford Street,
Cambridge Terrace from Oxford Terrace to Durham Street North,
Cranford Street and Westminister Street in St Albans,
Anzac Drive between Travis Road and New Brighton Road,
Chaneys on-ramp on the northern motorway,
Paisley Road Southbrook,
Hartleys Road Glentunnel,
Williams Street between Ohoka Road and Charles Street
And State Highway One between Main North Road South and Ohoka Road.