Appraisal number: 481 (2019)
Date issued: 12 Mar 2019
Triboard Construction System
The Triboard Construction System is a structural wall and ceiling panel system for use in the construction of Triboard panel houses. All other aspects of the design and construction of Triboard panel houses such as foundations, floors, roofs, joinery, cladding and interior finishing are conventional.
Triboard wall panels are 36 mm thick, and Triboard ceiling panels are 18 mm thick. Triboard panels are manufactured to consist of a strandboard core flanked by two outer layers of fibreboard.
Wall and ceiling panels are factory cut to shape and size, including window and door openings, by Triboard remanufacturers. All panel surfaces and exposed edges are pre-painted by the remanufacturer prior to delivery to site.
On site, the wall panels are connected by specified structural connectors to a ground floor platform of either concrete slab on ground or suspended timber-framed floor. The exterior wall panels are strengthened externally by vertical battens, and the lintels can be strengthened either with a double thickness or Triboard flitch plates.
For 2-storey houses, the upper floor construction is of standard timber framing and the upper floor wall panels connected to the floor.
Ceiling panels are installed over the wall panels and roof trusses are fixed over the ceiling panels. Conventional ceiling systems may also be used. The building is then completed using conventional construction.
The Triboard Construction System has been appraised for use in single-unit (detached) risk group SH housing that meets the scope of clause 1.1.2 of NZS 3604 with the following limitations:
- Buildings must be single or 2-storey.
- In NZS 3604 wind zones up to and including extra high.
- In all NZS 3604 earthquake zones.
- The ground-floor construction platform must comprise one of a concrete slab on ground or a suspended timber-framed floor constructed in accordance with NZS 3604.
- The first (upper) floor is a suspended timber floor constructed in accordance with NZS 3604.
- The first-floor live load does not exceed 1.5 kPa.
- Roof construction comprises trusses or roof framing in accordance with NZS 3604.
- Roof pitches must not exceed 35° nor be less than 5°.
- Triboard ceiling panel diaphragms not exceeding 8 m in length.
This Appraisal does not cover the general or wet area finishing to walls or ceilings.
The use of Triboard wall and ceiling panels in the following situations has not been assessed and is outside the scope of this Appraisal:
- Sauna rooms and the like where they may be exposed to sustained high humidity (greater than 95% RH) or liquid water.
- Where temperatures are in excess of 35°C over large areas for prolonged periods (e.g. ceiling heating installations) or in excess of 50°C in localised areas (e.g. the area adjacent to a fuel-burning appliance).
- In skillion roofs.
Always refer to the Appraisal in full and the technical literature.