Wood has a strong hygroscopic behaviour, with a strong variation of moisture content and dimension stability caused by modifications of the relative humidity of the surrounding air. The properties that define the behaviour of wood facing temperature and moisture actions were studied in this work. Linear thermal expansion, hygroscopicity, shrinkage (tangential and radial shrinkage coefficient) and hygric expansion were given special attention.An experimental device was designed for testing wood samples, red oak. A series of tests was performed including the determination of hygric expansion coefficient and the definition of the sorption curve. This research made possible the evaluation of dimensional stability of wood in transient conditions of relative humidity.
