Rethinking Risk: Government Refocuses Earthquake Prone Building Assessment
On 29 September 2025, the Government announced the retirement of the New Building Standard (NBS) rating for earthquake prone buildings (EPB) in favour of a more targeted, risk-based approach.
The Government estimates these reforms will save over $8.2 billion in remediation and demolition costs.
By focusing on actual risk rather than rigid metrics, the new system aims to balance safety with affordability.
These changes will be implemented through the Building (Earthquake-prone Building System Reform) Amendment Bill, which the Government intends to introduce as soon as possible.
Existing system
The NBS system assessed how existing buildings might perform in an earthquake relative to new builds, with those rated below 34% deemed earthquake-prone and subject to mandatory strengthening or demolition. Its broad and inconsistent application often captured low-risk buildings, leading to costly, complex, and frequently uneconomic remediation, particularly in lower seismic zones.
New system
The percentage based NBS will no longer be used to identify EPBs. Instead, buildings will be assessed based on specific risk profiles. Unreinforced masonry buildings with unsecured façades or walls facing public areas will automatically be deemed EPBs, whereas concrete buildings of three storeys or more will undergo targeted assessments focused on critical vulnerabilities.
Seismic Zones
Seismic zones have also been revised to reflect the latest scientific data. Notably, EPB status will be removed from all buildings in low-risk areas (Auckland, Northland, Chatham Islands), while coastal Otago (including Dunedin) shifts to medium risk.
The changes will remove approximately 2,900 buildings (55% of the current EPB register) from the system. Of the remaining buildings, around 1,440 will face more cost-effective remediation; 840 will require no remedial work; and only 80 buildings will need a full retrofit.
New levels of mitigation
Rather than the blanket 34% NBS threshold, mitigation requirements will vary by building type and location. The four levels include:
- Remaining on the public EPB register
- Façade securing
- Targeted retrofit
- Full retrofit
Remediation deadlines are also to become more flexible, with councils able to grant extensions of up to 15 years. Additionally, owners of low-risk buildings in small towns may have their EPB status removed entirely after completing basic façade work.
Streamlined compliance
To reduce compliance costs, seismic remediation only consent applications will be exempt from unrelated Building Code requirements, such as fire and disability access. EPBs changing use will only need to meet their assigned mitigation level.
The definition of priority buildings has also been narrowed to focus on masonry elements posing risks to public areas and buildings that could block emergency routes. Hospitals, schools, and fire stations will no longer be automatically prioritised, allowing agencies more time to plan upgrades.
Want to know more?
If you have any questions about these changes, please contact our specialist Property and Private Client Team.
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