Researchers are currently striving to advance possibilities for calculating the integrated phenomena of heat, air, and moisture (HAM) flows in buildings, while including the interactions that take place between the various building materials, components, and room air. Coupled HAM building simulation models have been developed by coupling numerical models that describe the airflow in the rooms of a building with HAM building component models. Computational fluid dynamics (CFD) models have been used to model the local indoor environmental conditions and convective surface transfer coefficients.

As an alternative to the use of CFD models, which are strongly limited by computer capacity, the applicability of subzonal airflow models for transient HAM building simulations has been investigated. This paper presents the modeling of the local indoor environmental conditions and convective surface transfer coefficients, focusing on prediction of the local interior surface heat and moisture transfer coefficients. The research showed that the developed model gives good agreement with the local convective surface transfer coefficients predicted from CFD. The main advantage of the presented subzonal airflow model is that the computational effort is relatively small, while predictions of the local surface transfer coefficients can be relatively accurate.