Ondol is a traditional underfloor heating system designated as a national intangible cultural heritage of Korea. The Cultural Heritage Administration (CHA) publishes a standard specification for the repair of cultural properties, including ondol. This standard specification is used as a guide for contractors who repair ondol in the field. However, the standard specification for ondol repair has some errors and is difficult to understand in the field. This paper proposes a revision of the standard specification for ondol repair. This study found that the standard specification for ondol repair has some problems in terms of the terminology and structure of ondol. These problems were sufficient to confuse ondol repairers in the field. Therefore, this study proposes to revise the standard specification to correct these errors and make it easier for ondol repairers in the field to understand. This study is expected to help recognize and preserve ondol as a cultural property and not just as a building.

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.