Following the Japanese way, a mixture of clay and cut grass was used. But due to miscommunication, sand was added to the first coat. In the second and third coats, cement was added to the mixture. In the Japanese way, a mixture of clay and cut rice straw grass are plastered over a Komai net as the first coat, making keys on the back side. Time has to be allowed for the first coat to dry, after which there will be some cracks which serve as keys for the second coat.
Some sand has to be added to the mixture of the second coat, and the surface cracks are smaller.
After drying, the third coat with more sand and finer fiber is applied. For a finishing surface, rice gruel or glue from sea weed, for instance, gloiopelitis, can be mixed as a bond. At the experimental house the 2 x 4 structure contains an air gap of about 14cm wide. A variety of porous material was used in separate sections to fill the gaps to avoid air convection. Later on each section will be compared with a heat rate meter.