Earthquake prone buildings
Under the Building Act 2004 Council is required to assess the earthquake risk of certain buildings within the district. Buildings that are determined to be earthquake-prone are required to be strengthened or demolished within specific timeframes set by the legislation. The Building (Earthquake-prone Buildings) Amendment Act 2016 introduced major changes to the way earthquake-prone buildings are identified and managed under the Building Act.
The system is consistent across the country and focuses on the most vulnerable areas and buildings in terms of people's safety.
In general, the provisions only apply to non-residential (commercial or industrial) buildings that could be potentially Earthquake prone, including:
- unreinforced masonry buildings
- buildings built before 1976 that are 3 or more storeys, or more than 12m in height
- buildings built before 1935
Managing earthquake-prone buildings
Alongside the change in legislation, a new national system for managing earthquake-prone buildings came into effect on 1 July 2017.
The new system affects owners of earthquake-prone buildings, local councils, engineers, other building professionals and building users.
The new system means:
- local councils must identify potentially earthquake-prone buildings
- owners who are notified by their local council must obtain engineering assessments of the building carried out by a suitably qualified engineer, this will confirm or disprove councils initial identification
- local councils use the engineering assessment to determine whether buildings are earthquake-prone, assign ratings, issue notices and publish information about the buildings in a public register
- owners are required to display notices on their building and to remediate their building.
The Building Act also divides New Zealand into three seismic risk areas – high, medium and low.
An overview of the system including seismic risk areas and time frames can be found on the Ministry of Business, Innovation and Employment (MBIE) “building” website.
What this means for Matamata-Piako
Our district spans is classed as a medium seismic risk area. That means our Council has between 5 to 10 years (from 1 July 2017) to identify potentially earthquake-prone buildings within our district.
For information on the methodology used, visit the MBIE website.
Council will inform building owners of a potential earthquake-prone status of their building. Building owners have 12 months to respond to this notice, that is, to confirm or disprove this status.
This will generally require an engineering assessment for their building.
If Council determines that a building is earthquake prone, it needs to:
- assign an earthquake rating for that building,
- issue an earthquake-prone buildings notice to the owner to display prominently on the building, and,
- publish the building information on the earthquake-prone buildings register.
Owners of earthquake-prone buildings who have received a notice must take action within set time frames. The time frames depend on whether the building is a priority building, and the seismic risk area that the building is located in.
Because the Matamata-Piako District is a medium seismic risk area, the timeframe to carry out seismic work on buildings identified as an earthquake-prone building is between 12.5 and 25 years.