ABSTRACT
This chapter focuses on the important aspect of the natural durability of the timber. It briefs the effect of photochemical, chemical, thermal and mechanical actions that are usually of secondary importance in determining durability and causing degradation. By far, the most important are the biological agencies, the fungi and the insects, both of which can cause tremendous havoc given the right conditions. In the absence of fire, fungal or insect attack, timber is really remarkably resistant and timber structures will survive, indeed have survived, incredibly long periods of time, especially when it is appreciated that it is a natural organic material with which we are dealing. The chapter also describes both fungal and insect attacks together with the important aspect of the natural durability of the timber. It then discusses another important aspect of durability of timber is its reaction to fire.
