Abstract
This paper intends to reveal the construction of the thatch roofing of the rice straw using the underlay of the Japanese silver grass. I researched for the “Yunohana Hut” had been built for producing the bath additive at the Myoban hot spring in Beppu City. The hut’s roof had been needed to the performance for keeping warm and discharging humidity, so the farmers had been kept making the thatch roofing. The thatched roof was built up from layers of the 150mm-thick underlay of the Japanese silver grass and 150mm-thick roofing of the rice straw. The Japanese silver grass filled the role keeping the room warming, and the rice straw was used as the roof material for good runoff of water.
