Solves one-dimensional coupled heat, air and moisture transport problems in a multi-layered porous wall. 1D-HAM is based on finite difference technique with explicit forward differences in time. Analytical solutions for the coupling between the computational cells for a given air flow through the construction are used. Moisture is transferred by diffusion and convection in vapor phase. No liquid water transport occurs. Heat is transferred by conduction, convection and latent heat. Climatic data are supplied through a data file with a maximum resolution of values per hour over the year. The program accounts for surface absorption of solar radiation.