The mortar-covered wall is often used for Washitsu. The mortar-covered wall is essential for the standard type of Washitsu known as Shin Kabe. This wall has the traditional Japanese method of plastering and finishes. It creates a unit wall, and has a characteristics fire-proof insulation and humidity control. Currently, wallpapers popular because they are simple to make, fast to construct and has a low cost. In recent years, people started giving consideration to nature and ecology. Among these popular materials used for Washitsu are the natural materials, the dynamite that has a high deodorant function and the Japanese plaster (Shikui), which is made of slaked lime.
The mortar-covered wall can be classified into the plaster, the Japanese plaster (Shikui), and the mud and fiber wall.
Japanese plaster (Shikui)
It had been used in castles and warehouses. Sand and glue are mixed into slaked lime, added hemp fibers, and kneaded with water to prevent cracking. It’s also used in walls of a closet.
It is superior in fire resistance, durability, and humidity control function. It controls the humidity, thus preventing mites and mold. It’s gentle to people because it’s made with natural materials which does not contain Hazardous Substances. Moreover, it does not pollute the environment.
Japanese planter is white, but there are colored planters that have added colored clay pigments. They offer amusing color variations. There are other variations of Japanese planters that are easy to construct like; wallpapers combined with charcoals, used natural loams or volcanic ash which has a humidity control function.
There are 2 types.
- “Gypsum plasters” which is one of the mortar-covered walls. It’s made by kneading the powder of mineral matter and water.
- “Dolomite plaster” which is made of the Muscovite. It gets hard when it comes into contact with carbon dioxide in the air. Gypsum plaster characteristics are; water hardened, condenses fast, less dry shrinkage, less cracks, and finished with beautiful white appearance. On the other hand, dolomite plaster is easy to knead. “Dolomite plaster” is easily available.
Mud wall is one of the traditional walls of Japanese architecture that is also a generic name of a plastering finish wall that is made of mud. It’s called “Kyoto wall” and has been used in a house in the style of a tea-ceremony pavilion. It’s spliced into three types by the final coat mud, and the diatomaceous earth wall made of natural materials is a kind of the mud walls.
What’s the fiber wall? It is a plaster that is made up of mixed pulp, paper fiber, or chemical fiber with glue and kneaded with water. It creates a mild atmosphere. It has a high sound absorbency, humidity control function and workability, but it’s rarely used because of its poor durability.