Consultation on proposed amendments to the Compliance Document for Clause B1 Structure
PROPOSED CITATION OF AS/NZS 1170 AND NZS 3101
The Department of Building and Housing will shortly be seeking feedback from interested parties on proposed changes to Verification Method B1/VM1 contained in the Compliance Document for Clause
In particular, the Department is proposing to cite the Loading Standard AS/NZS 1170 and the recently published Concrete Structures Standard NZS 3101 as means of compliance with the Building Code. The citation process is not automatic. The Building Act requires that the Department consult widely and prepare a cost-benefit analysis that assesses the impact of the new Standards on the building industry.
PROPOSED CITATION OF THE NEW LOADING STANDARD AS/NZS 1170
It is proposed that the new Loadings Standard AS/NZS1170, Structural Design Actions replace NZS 4203: 1992 General Structural Design and Design Loadings for Buildings in Verification Method B1/VM1. AS/NZS 1170 Structural Design Actions consists of the
- AS/NZS 1170.0: 2002 –
- AS/NZS 1170.1: 2002 –
Permanent, imposed and
- AS/NZS 1170.2: 2002 –
- AS/NZS 1170.3: 2002 –
Snow and ice actions
- NZS 1170.5: 2004 –
Earthquake actions –
The loadings standard is an important document as it specifies the general procedures and criteria for the structural design of buildings in limit state format. It covers design actions, combinations of actions, methods of analysis, robustness and confirmation of design. There have been changes to earthquake, live, wind and snow actions from those currently given in NZS 4203. The Department has been working with consultants to identify and give the reasons for all the changes, and a cost-benefit analysis has been carried out to investigate the impact of these changes on the building industry.
The cost-benefit analysis shows that overall there is little change with the increase in cost for buildings designed using AS/NZS 1170 being small. The study shows a significant net benefit when savings associated with such aspects as maintenance, damage, injuries and fatalities are accounted for.
A public consultation document, which will give background to and explain the changes and include the cost-benefit analysis, is being prepared and is expected to be available shortly.
PROPOSED CITATION OF THE NEW CONCRETE STRUCTURES STANDARD, NZS 3101: 2006
It is proposed that the Concrete Structures Standard NZS 3101: 2006, published in March 2006 by Standards New Zealand, replace the previous version, NZS 3101: 1995, currently cited in Verification Method B1/VM1. This Standard sets out the minimum material requirements for reinforced and pre-stressed concrete structures.
The Department is working with consultants to review the changes between these Standards and to prepare a cost-benefit analysis to assess the impact of the changes on the building industry. A public consultation document, which will give background to and explain the changes and include the cost-benefit analysis, is planned for release in September 2006. The consultation period will run for 8 weeks.
The Department will not make any decision about citing AS/NZS 1170 or NZS 3101 until such time as it has considered the comments received on both Standards. It is likely that any citation of the Standards in the Compliance Document will be subject to an introductory period to enable previously consented work to be completed and give designers time to become familiar with the Standards’ provisions. These aspects will be discussed in detail in the respective public consultation documents.
AVAILABILITY OF PUBLIC CONSULTATION DOCUMENTS
Selected commentators will be sent the public consultation documents as soon as they are available. Details of public consultation will be posted on the Department’s website www.dbh.govt.nz, in a future issue of Codewords and in the national newspapers.
Public consultation documents for both Standards will also be able to be downloaded, free of charge, from the Department’s website or a hard copy will be able to be obtained by calling the Department on 0800 242 243. A copy of the new Standards can be viewed at the Department’s Wellington offices or at major public libraries.