In November 2018, we released the revised (yellow) version of section C5 of the Seismic Assessment Guidelines.

The revised (yellow) version tells engineers how to best assess buildings with pre-cast concrete flooring, given what we now know about the issues with these buildings. It represents the latest technical information available to engineers.

Engineers should use the revised (yellow) version when carrying out assessments, with one exception. You should use the existing July 2017 version when you are assessing specifically whether a building is earthquake-prone under the legislation.

More information on how and when the revised (yellow) version should be used, and the nature of the changes, is available at

We’ve also produced two factsheets, developed with SESOC, NZSEE, NZGS and Concrete LS, to help engineers work with the revised (yellow) C5 and communicate with building owners about results.

Guidance for engineers on how to use the revised C5   |  201.4 KB

How to explain %NBS to a building owner   |  178.2 KB