San-ja is one of the main members consisting of the roof of traditional wooden buildings in Korea. In this study, the regional characteristics of the materials used in San-ja and changes of the materials over time were examined. To this end, 123 documents on the repair of wooden architectural heritage recorded since the 1950s were reviewed. It was found that there was a difference in the San-ja material by region because of the diversity in the conditions of material supply. For instance, bamboo was the most frequently used material in Jeollanam-do province because it was readily available. However, with the development of transportation and vehicle, the regional characteristics have disappeared. As a result, the material has been unified with bamboo now. This is because bamboo is specified as a representative material in the specification or the convenience of construction is prioritized. In addition, the social and economic conditions at the time of repair had an influence on the selection of the San-ja materials.

The purpose of this study is to connect the technics and form from ancient to Korea Dynast But in these period there is no buildings remains but paintings, fine arts, and stupas. In the historical materials there are many architectural form and signature revealings, so as a result these analysis, 1)The building showed in paintings of Silla, and Korea Dynasty reflect the architectural style their own Dynasty. 2)In detail, the architecture of Silla and Korea Dynasy was connected with Chinese architectur Liao, Song. But from the 8Century Koreans were succeeded the one of Silla Dynasty and had originility in architectural style. 3)The architectursl style in Silla and Korea Dynasty were very various and very rich content. And we must more serious study of historical materials so that we improve the ancient a middle age of architcture in Korea.