Technical Specification for the design of new buildings out for public comment

Published: 15 February 2024

Standards New Zealand has today released a draft Technical Specification for 'Structural design actions – Part 5: Earthquake actions – New Zealand' (TS1170.5) for public comment. The draft specification looks to provide updated engineering guidance to determine earthquake loadings when designing new buildings.

“Standards New Zealand and Engineering New Zealand were commissioned by the Ministry of Business, Innovation and Employment (MBIE) to develop a draft Technical Specification incorporating the science and insights gained from the updated 2022 National Seismic Hazard Model (NSHM),” said Malcolm MacMillian, National Manager, Standards New Zealand.

“The draft Technical Specification has been developed through a robust process using the skills, knowledge and experience of a committee of technical experts from across the building industry. We now welcome others to review the proposed draft and provide their feedback. Public comment will run for a 4-week period” says MacMillian.

“Once published, a Technical Specification should typically be reviewed after 3 years to decide whether to extend its use for a further 3 years, revise it, withdraw it or develop it further to become a standard.”

MBIE is encouraging people from across the engineering, building and property sectors to provide input into the public comment process being run by Standards New Zealand.

“The current earthquake loading requirements for new buildings are not changing with the release of this Technical Specification. Once published by Standards New Zealand, it will be able to be used by designers on a voluntary basis as one way of demonstrating compliance with the performance-based Building Code, through an alternative solution” said Dave Gittings, Manager Performance Building and Engineering, MBIE.

“It’s important to note that the Technical Specification does not change the requirements of the earthquake-prone building (EPB) system.  All seismic assessments, including voluntary seismic assessments, follow the same approach as for the national earthquake-prone building system and use the current standard NZS 1170.5:2004,” says Gittings.

The draft Technical Specification is a technical document. It has been developed to help engineers and designers voluntarily incorporate, into their designs, the results of new science in the NSHM. If the specification is followed, new buildings will be able to better withstand the range of earthquake shaking expected in different areas of New Zealand.

“The draft specification is intended for most new buildings such as offices, commercial buildings, and apartments. Other buildings, such as dwellings and timber framed buildings up to 2 storeys’ high are generally not affected because a different design standard is typically used.”

“The use of a technical specification provides the framework to ensure that technical content being proposed is adequately ‘road tested’ by New Zealand engineers, with the opportunity for them to provide feedback before the information is published in a New Zealand Standard or considered for inclusion into the Building Code,” says Gittings. 

Provide input on the draft Technical Specification 1170.5(external link) — Standards New Zealand's Consultation Hub

Public comment closes on 14 March 2024.

*Please note on the SNZ website there are 2 separate documents for TS1170.5:

  1. The main TS 1170.5 Structural Design Actions – Part 5: Earthquake actions draft
  2. The associated TS 1170.5 Structural Design Actions – Part 5: Earthquake Actions – Commentary draft

The purpose of the commentary is to provide background and additional information to the various provisions listed within the main TS 1170.5 draft, and references are provided for further reading and are given at the end of each section of the commentary.