SR244 Timber corrosion test methodology (2018)

BRANZ has developed a two-stage accelerated test methodology to determine the aggressivity of timber treated with different preservation chemicals towards mild steel and ho- dip galvanised nails.

In comparison with conventional techniques using high temperature and high humidity to accelerate corrosion, this method can more reliably simulate natural exposure as it establishes a more realistic environment inside the timber.

Results derived from this method also confirm that ACQ and/or CuAz treatments are more corrosive than CCA treatment, and the corrosion acceleration factors determined were similar to those obtained from field exposure tests. However, overestimation was still found, and possible approaches for further improvement are discussed.