Bamboo strips undergo an anisotropic dimensional expansion as they absorb moisture. This is shown in Fig. 3. The expansion in the width direction (i.e., along the circumference of the bamboo plant) was the largest, followed by the expansion in the thickness direction. The dimensional expansion along the length direction was 100 times smaller than that along the width. Like moisture content, the dimensional expansion of bamboo strips demonstrated hysteresis as the samples went through a moisture absorption–desorption cycle.