Above-Ground Durability Estimation in Australia. Results after 16 years exposure
L P Francis, J Norton
A program of research was established in 1987 to examine the above-ground durability of a selection of timbers that are commercially significant in Australia. Test samples were assembled in an L-Joint design and placed on exposure racks in a format to replicate joinery that is exposed to the weather above ground. Both painted and unpainted material has been exposed.
Test samples have been evaluated regularly over the sixteen-year exposure period, and although the trial is not yet complete, the research has highlighted and provided data on the effect of painting, the source of timber and the influence of location. Biodeterioration models are now being developed and as the exposure approaches completion, the models will be further refined using results that emerge for the more durable softwoods and hardwoods that are incorporated into the project.
As data is finalised for a particular species, it is to be submitted to the national standard for timber durability as well as design for durability programs currently underway in Australia.