Also written 鑪. The modern character is ro 鈩, and can mean furnace. Tatara is an ancient word meaning refinery. A building in which iron was refined. Sand, which contained iron, and also called magnetic sand satetsu 砂鉄, was refined in ancient times as early as the Yayoi period. Some tatara were circular maru-uchi tatara 丸打高殿, and some were square kaku-uchi tatara 角打高殿. The roof style depended upon the ground plan *heimen-zu 平面図, and on the tie beam construction.
Two roofing methods are called kiriage-zukuri 切上造 or inunobori-zukuri 犬登造 and two methods of arranging tie beams daimochi 台持 are called ōhira-zukuri 大平造 or kohira-zukuri 小平造. The Tetsuzan hitsuyō kiji 鉄山必用記事 (date unknown), states that pillars oshitate-bashira 押立柱 120-150 cm in circumference at eye level, and 9 m high, were erected in the four corners, 7.2 m apart. These pillars were called *hottate-bashira 堀立柱 and were inserted 3.6 m into the ground so that 5.4 m remained above ground. Then they were pushed outward until the tops of the pillars were 9 m apart. Four daimochi purlins were attached to the pillars to form a frame. Rafters called nagao 長尾 were leaned against the purlins and the lower ends were inserted into the ground. A gable roof with openings to allow air to enter and smoke to escape was constructed above the framework. Near the tatara were other smaller sheds or huts used to store iron, sand or charcoal. Living quarters were provided for the overseer motogoya 元小屋.