Consideration of underlying historical changes in house building materials in Okinawa prefecture

Abstract

This paper reviews the historical changes of house building materials in Okinawa related to construction methods and forestry policies. The traditional wooden houses construction in Okinawa had changed its trends to reinforce concrete houses. After the invasion of the Satsuma domain, Ryukyu Kingdom was utilized dual governed system from both Japanese and Chinese rules. This event had caused an economic difficulties and depletion of the forest resources. In the middle of 18th century, a drastic reformation by Sai On affected house construction that fixed societal ranks and the village landscape had changed into a checkerboard pattern. Conventional policies used in Okinawa of the Meiji period, was not managed accordingly and it caused degradation of forest resources that caused Okinawa to import timber from main islands of Japan. After the World War II, the United State Forces occupied Okinawa Island until 1972. Low-priced timber imported from Japan under import promotion policy forced between 1950 and 1958 had led to the promotion of wooden house constructions. The government substitute import materials to cement and plywood production, promote export activities to prevent trade deficit and support the increment of concrete houses. Besides the advancement in wood pre-cut- ting process, the government recently conducted domestic timber usage promotion that led to competition and market reclamation between timber suppliers and these factors had increased the development of the wooden houses construction over time.