Natural ventilation has an important effect on thermal behavior of a dwelling house in Japan. A calculation procedure was developed to predict the room air temperature and the heat load of Japanese housing. It includes the process to calculate natural ventilation precisely and quickly. The room air tempertures of two experiment houses were predicted by this procedure. The prediction was compared with the observation to valuate the accuracy and the validity of this procedure. The agreement between both is good and satisfactory.

* This paper was reproduced from the manuscript prepared for the Fourth International Symposium on the Use of Computers for Environmental Engineering Related to Buildings, 1983, Tokyo.
^*1 Chief Reseach Member, Building Services Division