ISA, IEP and DSA seismic assessments

Need an ISA, IEP report or DSA? Get expert advice on which type of seismic assessment would suit your requirements.

The Engineering Assessment Guidelines – Nov. 2018 provide a technical basis for seismic assessment of existing buildings in New Zealand.

The scope of an Initial Seismic Assessment (ISA), or Initial Evaluation Procedure (IEP report), typically includes the following:

  • Request and review the property files. The focus of the review is on the available drawings and
    design information for the subject building.
  • If site specific soil data is unavailable, GNS geotechnical maps will be used to identify the likely site soil class type.
  • Visual inspection of the accessible parts of the building. The purpose of the inspection is to verify that the plans within the property files are representative of the building, and document
    any visible structural features which may affect the earthquake performance of the building.
  • Assessment of the earthquake rating of the building in terms of percentage of the New Building
    Standard (%NBS) using the Initial Evaluation Procedure (IEP report). (Section B3.2 in accordance with Part A and
    Part B of seismic assessment guidelines.
  • The assessment will be accompanied by a report in accordance with the requirements of seismic assessment guidelines for ISA (Part B).
  • The report will be approved by a Chartered Structural Engineer experienced in seismic assessments.

The scope of a Detailed Seismic Assessment (DSA) varies for each building and a DSA overview is available in the seismic assessment guidelines Section C1.