Wooden-frame structures, with the capacity for continuous renewal, are key resources for urban regeneration and so comprise one of the most sustainable construction methods. This was true in the past for Japan, but following World War II, wooden-frame structures were demolished and replaced at a rapid pace. However, today, with Japan’s aging and dwindling population, the growing number of abandoned houses has become a socio-economic issue. In response to this crisis, local initiatives have been established to address this problem. Some novel design and management practices have arisen to restore the value of excess wooden-framed buildings. The purpose of this paper is to discuss the current design and renovation practices of vacant wooden-frame buildings in Japan, as well as to evaluate these practices in light of a sustainable future, by approaching this issue from the perspective of architects and designers and investigating their roles in these processes. The paper starts with the evolution of this building type from the past to the present. Data from in-depth interviews with specialists in wooden-frame construction as well as architects who are involved in the renovation of postwar timber dwellings are gathered and discussed. The emphasis here is on the expertise these specialists and architects have in successful cases of design and space management, as well as the incorporation of those buildings into the local community. Our case studies are located in different urban contexts; a regional city, a peripheral area of Tokyo, and central Tokyo. The findings highlight the crucial role of architects who mediate between benefits and drawbacks of current rehabilitation efforts, which are nevertheless still outnumbered by abandoned houses. Nonetheless, these experiences are crucial and valuable for the long-term viability of this building type in Japan.