Abstract
The load-bearing capacity of timber elements and systems is affected by moisture exposure. Varying moisture content in the ambient air and resulting non-uniform moisture profiles on cross-sections generate stresses perpendicular to grain because of restraint of hygroexpansion. This paper presents effects of indoor moisture diffusion in timber elements; moisture profiles within member and corresponding stresses are determined using finite element analysis and a relevant constitutive model. The stress variability is larger near the surface compared with the middle of a cross-section. No major differences are noticed between different climatic locations, but the induced stresses reach high levels above the characteristic strength in tension perpendicular to grain. It appears that indoor moisture effects differ insignificantly between the different climatic locations investigated in this study.