Demolition operation will clear the central business district (CBD) to make it safe

The CBD has been flattened, and many offices have sunk into the ground due to liquefaction. Similarly some suburbs. There is going to be next to no available office space available for months at least, probably years.
Temporary office solutions:
http://memia.com/blog/general/2011/christchurch-earthquake-business-recovery-temporary-office-solutions