Cannabis as a traditional building material

In the wisdom of making the most of what is around us for daily life, hemp has been used as a building material for Japanese houses. Ogara, the woody part of hemp after the fibers were removed, was used as thatch underlayment for roofing and to prevent thatch from breaking. Ogara is strong and lightweight. In 1976, Shirakawa-go was selected as an Important Preservation District for Groups of Traditional Buildings as a gassho-zukuri village of more than 100 buildings of various sizes, and in 1955, it was registered as a UNESCO World Heritage Site (cultural heritage) together with Gokayama as Shirakawa-go and Gokayama’s gassho-zukuri villages. If you look under the thatched roofs of Shirakawa-go, a UNESCO World Heritage Site (cultural heritage), you will see many cannabis plants. Cannabis used for thatching at Ouchi-juku in Fukushima Prefecture, which was selected as an Important Preservation District for Groups of Traditional Buildings in 1981, has been designated as “Kanuma Noshu Hemp Shells (Ramie Shells) of Kanuma Field” by the Agency for Cultural Affairs as part of its “Hometown Cultural Properties Forest System Promotion Project. It is designated as such. In addition, not only as a roofing material for those buildings, but also as a material for earthen walls and plaster, as with straw, hemp-sheaf, a fiber waste from hemp, has been used by kneading it with lime and funori (funori). In recent years, hemp has begun to be used as hemp cleat, hemp block, hemp panel, and hemp insulation material, which are attracting attention not only in traditional architecture but also worldwide as eco-friendly materials.