NZSEE Risk Rating

In their 2006 document ‘Assessment and Improvement of the Structural Performance of Buildings in Earthquakes’ the New Zealand Society for Earthquake Engineering (NZSEE) presented a risk assessment framework on the following lines and recommended that buildings be strengthened to at least 67% NBS and preferably to 100%.


Risk assessment

Less than 34

High risk


Medium risk

Over 67

Low risk

These recommendations have been very influential and have set in motion forces that have in many cases compelled building owners to strengthen their buildings to unnecessary high levels.

However, these risk assessments and recommendations are not based on any life risk analysis, or on any consideration of the costs and benefits of reaching the recommended strengthen levels. Our analysis (see the document The NZSEE’s % NBS risk measurement framework: Why it doesn’t work) shows that the NZSEE risk assessment framework is fundamentally flawed, and that in many cases classes of buildings are being represented as high risk when it is clear that they are not.

We think that the NZSEE should withdraw its rating system and recommendations, and that other parties (including MBIE) who have promoted them should withdraw their support.


EBSS will be asking the NZSEE to either demonstrate that that their assessments and recommendations are robust, or withdraw them.  We will also be asking parties who have promoted the framework to withdraw their support. Our objective is to help replace this flawed system with a more robust methodology that will provide building owners and users with life safety risk information.

If the framework is not withdrawn owners have a legal remedy.

Building owners who have suffered economic damage because of the NZSEE’s statements about building risk and flawed advice on strengthening strategies are entitled to seek compensation for their loses. Under common law  we believe that the NZSEE’s statements are a ‘slander of title’. A slander of title involves a party falsely disparaging another's property which impacts on the value of that property. The owner could be entitled to damages for the loss of economic value or for expenses unnecessarily incurred. Actions could be taken against the NZSEE, the parties who contributed to NZSEE (2006), and other parties who have promoted the risk assessment framework. Actions could also be taken against MBIE and MBIE employees for publishing the NZSEE recommendations and promoting their use.

Slander of title claims might also be taken against local authorities who have designated buildings as being earthquake prone when they are not.

EBSS will be assisting owners to seek legal redress for harm already done, or that continues to be done as long as the NZSEE assessments are extant.