How the earthquake-prone building system works

Seismic risk areas

The Building Act 2004 divides Aotearoa New Zealand into 3 seismic risk areas: high, medium and low.

These risk areas help decide how much time territorial authorities (councils) and building owners have to identify, strengthen or remove EPBs.

Changes to seismic risk areas in 2026

• There are no longer any designated EPBs in Auckland, the Chatham Islands, or in the upper North Island low seismic zone.
• Parts of the South Island (including coastal Otago) and Stewart Island that were previously in a low seismic zone have now moved to a medium seismic zone.

For more information, including a map of the updated seismic zones, see:

Changes to the earthquake-prone building system

Deadlines and timeframes

Each seismic risk area has different timeframes for carrying out seismic work.

The table below shows how long building owners have to carry out work after they receive an EPB notice.

*Time starts from the date the earthquake-prone building notice is issued, unless an extension is granted.

Buildings in the low-risk seismic zones are no longer part of the earthquake-prone building system. Territorial authorities cannot identify new EPBs in these areas.

Buildings covered by the earthquake-prone building system

The EPB system applies to most non-residential buildings and some larger residential buildings.

A residential building is covered by the EPB system if it is in a medium or high seismic zone, it is at least 2 storeys tall and either:

• contains 3 or more household units, or
• is used as a hostel, boarding house, or other specialised accommodation.

Buildings excluded by the earthquake-prone building system

The EPB system focuses on buildings that pose the greatest risk to public safety.

It does not apply to standalone houses used by 1 or 2 households.

It does not apply to any buildings in Auckland, the Chatham Islands, or the upper North Island low seismic zone.

Some types of buildings are also excluded, including:

• farm buildings
• retaining walls
• fences
• some monuments
• wharves
• bridges
• tunnels
• storage tanks.

Farm buildings

Farm buildings are excluded from the EPB system because they are expected to pose a lower risk if they fail.

Farm buildings are located on a farm and:

• are mainly used for farming activities, or
• support those activities.

Examples of farm buildings include:

• stables
• woolsheds
• cowsheds
• hay barns
• herd homes
• implement sheds
• milking sheds
• fattening units
• ancillary buildings
• storage buildings.

Some buildings on farms are more like industrial or manufacturing facilities and are not considered farm buildings. Examples include:

• manufacturing plants
• packhouses
• vineyards.

These facilities are usually modern buildings and are unlikely to be earthquake-prone.

Parts of buildings

Engineers assessing potentially EPBs must consider vulnerable parts of buildings as well as the overall performance of the whole building.

A part is an individual building element. For example, an unreinforced masonry parapet may pose a risk to life if it falls, or causes another part of the building to fall, during a moderate earthquake.

More information about how engineers assess and report on parts of buildings is available in The methodology to identify earthquake-prone buildings.