Natural environmental factors affecting the site selection of traditional Japanese folk houses in the Shikoku region

The site selection characteristics of traditional Japanese folk houses (in Japanese, minka ) reflect residents’ adaptation strategies to different natural environments. This study investigates the relationship between natural environmental factors (e.g., topography and climatic conditions) and minka site selection in the Shikoku region, focusing on Tokushima Prefecture. Based on a literature review, field surveys, geographic information system tools, and meteorological data, this study analyzes the distribution of minka using historical records, topographical maps, and climatic characteristics. The results show that minka are predominantly located in areas with moderate annual precipitation (<2000 mm/year), mean temperatures of 13–16 °C, and low wind speed conditions with values below 0.2 m/s. In Tokushima, >63% of minka are situated within 300 m of a river, and they strongly favor south-facing slopes (43% of cases), elevations below 200 m, and gentle slopes (<15°), indicating strategies for optimizing thermal comfort, agricultural efficiency, and flood resilience. Principal component analysis identified elevation, precipitation, distance to rivers, and slope direction as the key factors explaining minka distribution. These findings also reveal the influence of historical production systems, such as indigo cultivation, and geopolitical factors on settlement patterns. By integrating geospatial, climatic, and architectural analyses, this research provides a transferable framework for assessing the environmental resilience of traditional built environments and contributes to interdisciplinary discussions on sustainable technology, cultural heritage conservation, and climate-responsive planning in vulnerable regions.