The New Zealand construction industry is moving away from solvent based treatments, with H3.1 no longer an acceptable solution for solid timber framing, and Lumberworx is leading the charge for engineered wood products suppliers.
Lumberworx supplies all its products at H1.2 and has produced a helpful bulletin to help everyone get up to speed with the changes.
Lumberworx I-Beam (LIB)
The Lumberworx I-Beam (LIB) is treated to H1.2 hazard class. This is achieved by fabricating with all components treated to H1.2 by full penetration methods to the retention levels prescribed in NZS3640:2003 (including amendment 5). The LIB can be installed within the building envelope wherever H1.2 hazard class is specified in NZS3602:2003. This includes sub floor, mid floor and roof spaces, while also being fit for purpose under wet areas.
The H1.2 treatment is a New Zealand first for I-Beams, and is another step in eliminating solvent based treatments from the building site.
Laminated Veneer Lumber (LVL)
All LVL distributed by Lumberworx will be treated with the innovative Lonza AZOTEK™ treatment to H1.2. LVL is not suited to external applications where exposed to weather.
This H1.2 treated product can be used with confidence wherever H3.1 LOSP is specified or anywhere in the building envelope where H1.2 Boron treated sawn timber can be used. (Refer to MBIE/DBH Timber Treatment for enclosed framing guide).
This glueline and face treatment has greater efficacy than H3.1 LOSP and must be accepted by consenting authorities because it is referenced in B2/AS1.
Laminated Strand Lumber (LSL)
LSL is treated with ZB (zinc borate) and can be used with confidence anywhere in the building envelope where H1.2 is permitted. (Refer to MBIE/DBH Timber Treatment for enclosed framing guide – Pink is Tough).
The Lumberworx GL17c beams are treated in Australia with boron to the retention levels required in NZS3640(A5). Slash Pine is equal to Pinus Radiata in durability so is treated to the same level as radiata.
Some Australian imported Glulam still uses H3 LOSP treatment but this no longer meets the NZBC as it is not referenced in the standards or B2/AS1. Lumberworx does not import this product.