sogi-ita 殺板

Also written 曾木板 or 枌板; also called hegi-ita へぎ板. A thinly cut wooden shingle, 3 mm thick, and usually 30 cm x 9 to 12 cm wide. This word and its meaning appear in the Man'yōshū 万葉集, a compilation of poetry begun by Emperor Nintoku 仁徳 (4th century) and continually added to until the reign of Junnin 淳仁 (r. 758-64) demonstrating that such roofing was common in the 7th-8th century. Shops in Kyoto and Nara were also roofed with sogi-ita and secured with bamboo nails called kuredome 榑止. Bamboo and/or thin logs and stones were laid over the shingles to hold them down.