Revitalizing Japan’s Vacant Houses: A Sustainable Approach Through Adaptive Reuse

Adaptive reuse of vacant houses in Japan offers an innovative and sustainable solution to the increase in vacant houses. This approach aligns with principles of sustainable architecture and the circular economy by reducing waste, lowering energy consumption, and extending the lifecycle of existing structures. This study uses purposive sampling, analyzing 262 adaptive reuse cases across Japanese prefectures through partial surveys, municipal records, and online maps. K-prototype clustering identified three distinct patterns. Cluster 1 emphasizes modern businesses, such as food, beverage, and accommodation services, within urban areas to address the needs of densely populated regions and tourist hubs. Cluster 2 blends urban and rural contexts, balancing historical preservation with modern functionality. Cluster 3 highlights rural and scenic accommodations that cater to tourists seeking cultural immersion and authentic experiences, despite challenges like low population density and limited accessibility. These findings contribute to the theoretical understanding of adaptive reuse as a key strategy for repurposing underutilized spaces, promoting both economic and social resilience. In practical terms, it demonstrates how adaptive reuse advances circular economy objectives by preserving cultural heritage, enhancing environmental sustainability, and creating economic opportunities. Further investigation is needed to unlock the unexplored potential of adaptive reuse in broader contexts and functions.