Canterbury Earthquakes Royal Commission Te Komihana Rūwhenua o Waitaha Canterbury Earthquakes Royal Commission – Te Komihana Rūwhenua o Waitaha

Those who lost relatives and friends in the 22 February earthquake can be assured that there will be a very thorough inquiry into the failure of buildings that resulted in loss of life.
Chair, Justice Mark Cooper

Notice of Issues

Six principal issues arose under the Commission’s terms of reference. Public Expressions of Interest were sought from parties interested in these issues. We also commissioned technical reports on a number of them. These reports were independently peer reviewed by eminent experts in the relevant fields and then published on this website. 

Issue 1 – Seismicity

  • a. New Zealand’s geological setting
  • b. Seismological model for New Zealand, and in particular for Canterbury
  • c. The nature and severity of the Canterbury earthquakes
  • d. Geotechnical knowledge and its implications for foundation types
  • e. Conditions likely to give rise to liquefaction

Issue 2 – Inquiry into buildings in the Christchurch Central Business District (CBD)

  • a. The Royal Commission is required to establish a reasonably representative sample of buildings in the CBD and to then use this sample as the basis for answering a number of very significant questions that arise from the earthquakes.  This representative sample will include the Canterbury Television (or CTV) building, the Pyne Gould Corporation (or PGC) building, the Forsyth Barr building and The Hotel Grand Chancellor building, and:
    • Any building within the CBD which failed and caused the death of anyone
    • A selection of buildings which withstood the Canterbury earthquakes
    • A sufficient range of buildings to cover:
      • the different structural types and forms of buildings in the CBD
      • the different construction materials used
      • the design and availability of safety features including escape routes, such as stairs
      • the different dates of design and construction, including heritage buildings
      • buildings that had been retro-fitted to improve earthquake resistance
      • buildings which had been identified as “earthquake-prone” on or before 4 September 2010
      • different foundation types and underlying soils
      • different types of building usage
    • Buildings which will enable the Royal Commission to determine the effectiveness of both damage assessments made and remedial work carried out between the 4 September 2010 and the 22 February 2011 Canterbury earthquakes
  • b. In relation to this sample, the principal questions the Royal Commission will then address are:
    • Why did some buildings fail severely, in some cases causing injury and death, while others did not
    • Whether there were particular features, or patterns of features, that contributed to the failure of buildings
    • The nature of foundations and the soils on which these buildings were located and how these affected the performance of the buildings
  • c. In relation to all or some of the buildings inquired into under paragraph (b) above (but including the four specified buildings):
    • Whether those buildings complied with any applicable earthquake risk and other legal and best-practice requirements, both when designed and constructed, and on or before 4 September 2010
    • Whether, on or before 4 September 2010, those buildings had been identified as “earthquake-prone” or were the subject of measures to make the buildings less susceptible to earthquake risk
  • d. In relation to the buildings inquired into under (c) above, the nature and effect of any assessment of them, and of any remedial work carried out on them, after the 4 September 2010, or after the 26 December 2010, but before the 22 February 2011 Canterbury earthquakes
  • e. The policies adopted by the relevant authorities in undertaking the assessments made of buildings after 4 September and 26 December 2010

Issue 3 – Inquiry into legal and best-practice requirements

The adequacy of the current legal and best-practice requirements for the design, construction, and maintenance of buildings in CBDs in New Zealand to address the known risk of earthquakes and, in particular:

  • a. The extent to which the knowledge and measurement of seismic events has been used in setting legal and best-practice requirements for earthquake-risk management in respect of building design, construction and maintenance
  • b. The legal requirements for buildings that are “earthquake-prone” under section 122 of the Building Act 2004 and associated regulations, including:
    • The buildings that are, and those that should be, treated by the law as “earthquake-prone”
    • Existing buildings that are, or should be, required by law to meet the seismic standards for the design, construction and maintenance of new buildings
    • The enforcement of legal requirements
  • c. The requirements for existing buildings that are not “earthquake-prone” and do not meet current legal and best-practice requirements for the design, construction and maintenance of new buildings, including whether, to what extent, and over what period, they should be required to meet those requirements
  • d. The roles of central government, local government, the building and construction industry, and other elements of the private sector in developing and enforcing legal and best-practice requirements
  • e. The legal and best-practice requirements for the assessment of, and for remedial work carried out on, buildings after any earthquake, having regard to the lessons from the Canterbury earthquakes
  • f. How the conclusions reached in relation to paragraphs a-e above compare with the position in any other relevant countries

Issue 4 – Change of New Zealand Design Standards/Codes of Practice over time

Changes in design philosophy for earthquake resistance as reflected in New Zealand design standards over the past 75 years, having regard to:

  • a. The levels of seismicity that have been used to calculate the required design strengths and the deflections associated with the design level earthquake
  • b. The methods used to determine design forces and the methods used to calculate the strength required to resist them
  • c. The assumptions made regarding the stiffness of building elements and the calculation of displacements induced by the design earthquake
  • d. The design principles used to calculate deflections caused by a major earthquake, without collapsing or endangering life

Issue 5 – Development of technical expertise in the design and construction of seismic resistant buildings

  • a. Academic and in-practice training of seismic engineers
  • b. Research to advance seismic performance
  • c. The application of technical knowledge in setting legislative and regulatory requirements

Issue 6 – Future measures

New buildings

  • a. Necessary changes to current design practice
  • b. Consideration of new technologies, including their cost

Existing buildings

  • a. New and recent methods of retro-fitting
  • b. The appropriate level of compliance with new building standards or alternative performance criteria, taking into account the cost of compliance