A review of post-earthquake building control policies with respect to the recovery of the Christchurch CBD
The Canterbury earthquake sequence was particularly disruptive for building owners and businesses located within the CBD. The initial damage to buildings in the relatively moderate September 2010 earthquake was surpassed by the significantly more damaging February 2011 event, challenging the way in which engineers have traditionally considered earthquake recovery.
Internationally, re-occupation of buildings following an earthquake has been based on the need to get businesses operating from buildings that are rapidly identified as having suffered minor structural damage. However, following the February 2011 earthquake, the shift in risk profile was reflected by limiting re-occupation unless it could be shown that the building also had a minimum capacity to resist earthquakes. This challenges the balance between continuing function and safety in the traditional post-earthquake evaluation process.
The timeframe for commencement of repairs has a significant impact on the speed of recovery. The importance of well defined regulations was highlighted in the well insured Christchurch building market, where legal arguments halted repairs in many instances. There is also a clear need for a modified, streamlined building consent process for the repair of earthquake damaged buildings.
This paper looks at the various building control policies enacted during the Canterbury earthquakes, and their effectiveness in aiding the recovery of the Christchurch CBD.
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