An overview of recent studies involving the thermal modification of hardwood species
D Jones, M Gaff, F Kacik
This paper outlines recent activities related to the thermal modification of hardwood species, and particularly to tropical hardwood species. Timber demand is ever increasing, but this is being limited by the necessity to protect virgin forest stands. As such, the majority of supply of popular species is being met from juvenile short rotation stands. The limited age from these stands often plays a significant role in the natural durability of the supplied material. This can lead to premature failure in service. Herein are described several series of experiments that consider the thermal modification of a range of species, such as oak, teak, meranti and acacia. The thermal modification, based on the ThermoWood® principle, was carried out at temperatures 160 °C, 180 °C and 210 °C. Results within relate to the chemical composition of the species and noted colour variations as a result of treatment. Additional work outlines ongoing studies into improving the fire resistance of selected species through the use of fire retardants (both synthetic and naturally occurring).