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Technical reports

Reports on building-related topics published by the Department.

Hollowcore Floor Overview Report

Hollowcore Floor Overview Report in PDF format [PDF 121 KB, 23 pages].  

What sort of publication it is: Black and white brochure
Who it's for: Building designers, building officials, manufacturers and owners
What it contains: The Hollowcore Floor Overview Report has been produced by the Department to further update designers, building officials, manufacturers and owners of the results of its investigations into the use of hollowcore flooring in New Zealand and its likely performance in strong earthquake shaking.

Studies were commissioned by the Building Industry Authority and continued by the Department following a full-scale simulated earthquake test at the University of Canterbury in October 2001. The main topics it covers are:

  • surveys and investigations
  • survey findings
  • discussion and conclusions on the key issues
  • recommended action.

How much it costs: Free
How to get it:

Report on Grade 500E steel reinforcement

Report on Grade 500E steel reinforcement [PDF 4.6 MB, 113 pages].   What sort of publication it is: Black and white book
Who it's for: Building designers, building officials and construction contractors
What it contains: An investigation into the concerns raised in 2003 that Grade 500E reinforcing steel might not be fit for its purpose as reinforcing when subject to design earthquake loading in ductile reinforced concrete structures. The main topics it covers are:
  • a summary of the investigations
  • a summary of the key issues identified
  • comments and conclusions on the key issues
  • recommended action.

How much it costs: Free
How to get it:

Investigation into TimberSaver Treated Framing Timber - Final Report

 

What sort of publication it is: Black and white brochure
Who it's for: Building designers, building officials, manufacturers and owners
What it contains: This is the final report on the issues raised in the media in July 2005. This report follows the interim report released in August 2005. This report is based on tests undertaken by BRANZ Ltd, as well as other information gathered following the release of the interim report. This report concludes that:

  • providing the TimberSaver treated framing timber was and is used in accordance with the conditions of use, it will meet the performance requirements of the Building Code;
  • the conditions of use are practical, and not dissimilar to those of other treated timber products; and
  • manufacturers and builders’ merchants need to ensure a practical means of allowing builders and building officials to identify how long timber treated with TimberSaver has been exposed to weathering.

Specific recommendations are that manufacturers and builders’ merchants:

  • ensure that prior to being used that treated timber, is transported, handled and stored such that it is protected from weathering, where this is necessary to protect the efficacy of the treatment system;   and
  • provide information to users, with each sale, about how to use the treated framing timber, and its conditions of use.

How much it costs: Free
How to get it:

Timber Treatment Survey Report

Timber Treatment Survey Report.  

What sort of publication it is: Black and white brochure
Who it's for: Designers, builders, timber processors and merchants, regulators, and researchers
What it contains: This report presents the findings from a survey of the building industry on the preservation treatement of framing timber.  It is made available in conjunction with a short summary in the Codewords Issue 29.

The Department had met industry representatives in late 2007 who expressed that selections for framing treatment were too complex and changes were required. There was also clear indication that LOSP (light organic solvent preservative) treatments were increasingly ‘out of favour’.

The survey was designed to gather wider comment from industry with questions covering: 

  • choices for treated framing
  • handling LOSP timber
  • boron treatments
  • weather exposure
  • timber identification and quality assurance

The survey report includes the full

  • survey responses with analytical graphs
  • comments as received and grouped into key themes.

The responses to this survey will help inform an intended programme of amendments, especially to NZS 3640 and NZS 3602, and to other industry guidelines and Codes of Practice as appropriate.  The Department is commissioning a testing programme on the performance of H3.1 boron-treated framing as a possible alternative to LOSP

How much it costs: Free
How to get it: