Abstract
The objective of this paper is to confirm appropriate cross ventilation for realizing a comfortable indoor environment in residential houses during the Showa era before WWII. Cross ventilation is one of the physical factors in architectural design. "ASAHIJYUTAKUZUANSHU" is a typical style book for Urban Dwellings and Houses in that era. About one hundred housing plans for small families were listed in it. Architects in those days tried to take cross ventilation into account in their housing design. The plans for the houses represented in the book were analyzed from the viewpoint of cross ventilation. In order to evaluate cross ventilation, the "effective area index" was newly defined. Consequently, it was found that the effectiveness of the ventilation depended on the arrangement of an entrance and living room, and the effective area related to indoor airflow.
