The Efforts to Develop Longer Life Housing with Adaptability in Japan

In the past, the average life of housing in Japan had been around 30 years vs. 77 years in the UK. In the late 1970's, the Japanese government and private sector started research and development projects to design and build longer life housing that is adaptable with time, such as the Kodan Experimental Housing Project (KEP) and the Century Housing Project (CHS). We have been researching the outcomes of those experimental projects to determine whether the attempted adaptability has worked or not over the thirty plus years that people have been living in them. We found that the housing with adaptable infill has been able to adjust to changes in family size and lifestyles in the KEP and CHS projects and have reported on it at several CIB conferences. The Japanese government enacted the Long Life Housing Law in 2009 to extend the life of Japanese housing and increase its adaptability over time. The law's technical guidelines require that continuous efforts be made to improve adaptability to extend the life of housing, and the amount of housing built based on these guidelines has been increasing. In the near future, Japan will have a shortage of construction workers. Therefore, an infill system that can be installed by unskilled labor needs to be developed. We need to compensate for the coming labor shortage in the construction sector by improving its relatively low productivity. We think it is becoming more important to design and construct buildings which require less skilled labor. At the same time, the infill of those buildings needs to be simple like furniture, easy to install on site, and easy to replace by residents and users. The concept of Open Building will play an important role in Japan's future.