Photodegradation and weathering effects on timber surface moisture profiles as studied using dynamic vapour sorption

The moisture sorption kinetic profiles of Scots pine (Pinus sylvestris) earlywood and latewood were studied using a Dynamic Vapour Sorption apparatus and the equilibrium isotherms determined. The samples were chosen to give an insight to the effects that photodegradation and weathering have on the moisture behaviour of the surface layers of timber. Samples were subjected to indoor and outdoor exposure regimes. Significant differences were found between the sorption isotherms of exposed and unexposed wood, as well as with the sorption kinetics profiles. The reasons for these differences are discussed.