This study conducted a quantitative analysis of the number of water usage spaces and of the changes in their floor area ratio by using a space analysis program. The analysis results were then examined from a socio-cultural perspective to see how the water usage spaces, which had been linked to the outdoor space in the traditional Korean housing, affected changes in apartment house plans and subsequent changes in the housing culture, as they moved to the inside of the apartment house. It was found that water usage spaces greatly affected the entire unit floor plan of apartment housing, undergoing various changes in correlation with the changes in society and daily life.
