Closed-form solutions for the heat and moisture distribution given by the Luikov system of partial differential equations have been obtained by using periodic solution approach. Boundary conditions of the third type valid for capillary porous structure have been used to find the unknown constants. Calculations have been performed for Spruce wood, the properties of which were known. The results show that moisture reduces the temperature distribution between outside and inside by 2-3 degrees C which is in conformity with the earlier results of Hall.