TABLE OF CONTENTS A mathematical model for predicting moisture sorption rates at building surfaces is presented. The governing heat and moisture transfer equations are solved by an implicit finite-difference method. The effects of surface coatings are included in the formulation.
Laboratory experiments were conducted to verify the model. Disk-shaped specimens of unpainted gypsum board, gypsum board painted with a latex paint system, and unpainted white pine were used. Sorption isotherms and diffusion coefficients for these materials were independently measured. The specimens were initially conditioned to a uniform moisture content and then moved to an environment with a lower relative humidity. The moisture transfer rates at the surfaces of the specimens were determined as a function of time and compared to predictions by the mathematical model.
The validated mathematical model was used to estimate sorption rates at interior surfaces of a building during a...
