Specialty Timbers New ZealandSearch technical reports
Investigation into TimberSaver Treated Framing Timber - Final Report
By Department of Building and Housing, July 2007.
Download investigation-into-timbersaver-treated-framing-timber (pdf)
Executive summary
Findings:
- 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.
From page 8 in this report:
31. BRANZ Ltd was also contracted to undertake weathering testing. It did this by three means:
- Taking sample frames, and placing them at the BRANZ Ltd exposure site at Judgeford for between 10 and 12 weeks
- Taking small scale frame samples and subjecting them to accelerated weathering by cyclic rain exposure using a ‘Cyclic Rain Rig’;
- Taking small scale frame samples and subjecting them to accelerated weathering by continuous high humidity conditions using a ‘fog room’.
32. The purpose of the three test regimes (natural weathering, cyclic rain exposure and fog room testing) was to determine how much of the TimberSaver boron treatment was leached from the sample frames. Establishing this would provide data about the
efficacy of the treatment process after timber treated with TimberSaver boron had been exposed to rainfall on a construction site.
33. It is important to note that a condition of use associated with timber treated with TimberSaver boron is limiting the exposure of the timber to weathering to a period of two months.
No posts yet
Add a post