Above-ground field tests undertaken in New Zealand
M E Hedley, D R Page, J B Foster, B E Patterson
In addition to "standard" L-joints, above-ground test material exposed at the NZ FRI test site includes treated and untreated decking units, Y-joints, fence battens and weatherboards either with or without additional protection from surface coatings. The latter tests bridge the gap between "model" test assemblies, such as L-joints, and services tests. Most tests are of preservative-treated radiata pine using proprietary formulations which were approved for above ground use at the time when each test was established. Other tests are natural durability tests to determine the suitability of those species, in terms of durability and mechanical properties, for above ground use without preservative treatment. The first tests were established in 1952 and results from those and subsequent tests have been used during periodic amendments to NZ wood preservation standards and specifications. The purpose of the different tests is described as well as pertinent results from them to illustrate their value.