The need for optimizing energy use in building is drawing designers back to natural environmental controls. Natural air movement caused by wind is the principal cooling method in hot and humid climates. Natural airflow through multiple-unit housing was investigated using a wind tunnel with smoke showing airflow patterns. The planes and sections of model buildings are two cases, respectively. Photographs of smoke lines around models are taken as records of results. The airflow rates through openings are estimated by the number of smoke lines through the models.