Problems related to humidity are usually treated as an equilibrium moisture transfer phenomenon at the finite element in the ordinary building materials at recent studies. For porous materials, it is required that the problems are discussed as a nonequilibrium transfer phenomenon at the element within. We defined the local moisture transfer coefficient as the nonequilibrium transfer and developed the procedure to identify it in this study. The coefficients are obtained experimentally for a wood board under the step-up condition of moisture absorption. Furthermore, variations of moisture absorption rate by numerical simulation with simultaneous heat and moisture transfer equations considered the local moisture transfer agree with those by experiment closely.
