ABSTRACT: Various models and tools have been invented to fulfill the different needs in natural ventilation study. Models and methods ranges from a very simple empirical algorithm to calculate airflow rate to a sophisticated computational fluid dynamic (CFD) techniques, in solving the Navier-Stokes equation. Yogou Li (1994) classified the available methods to estimate air flow into three categories. They are analytical method, use of a full scale model and CFD technique. Heerwagen et. al. (2000) classified the available methods into four categories which are field measurement, physical modeling, computer simulation and simplified methods. Wang (1996) categorized the main method for studying natural ventilation due to temperature difference through two main methods. They are physical and virtual experiment methods. The physical experimental method includes scale measurements or field experiment. Meanwhile, virtual experimental method is referred to as CFD modeling base on numerical equation.