A kotatsu table is a low table with a wooden frame covered with a blanket or futon. It is a table top, and underneath is a heater that is usually built into the table itself. This table is typically used as a dining table in Japanese households.
In the 14th century, during the Muromachi period, every Japanese home had a charcoal hearth or fireplace made of bricks or stone.
This was called an irori. The irori served as a hearth. Later, the Japanese improved this hearth by adding a wooden platform with a blanket over it to trap the heat. This became known as hori-kotatsu or hori-gotatsu with hori meaning ditch, ko meaning fire, and tatsu meaning foot warmer.
In the 17th century, during the Edo period, the hori-kotatsu was modified by creating a sunken irori around which the wooden platform was placed. The Japanese draped a blanket on it to trap the heat.
The kotatsu table became more portable with the invention of tatami, a material used in Japanese homes. A pot served as a substitute. The Japanese simply placed this on the tatami, making it much easier to place the kotatsu anywhere. This was then called oki-gotatsu, where oki means placement.
In the 20th century, the kotatsu table was made completely portable. An electric heater was introduced by placing the heater under the table top of the wooden frame. Nowadays, the wooden frame can be replaced with other materials such as plastic.
Japanese houses, unlike Western ones, are not quite as well insulated. There is no central heating. Due to the structure and design of most Japanese houses, central heating is very expensive in Japan.
Therefore, instead of central heating, the Japanese have chosen spot or space heating as their heat source. At this time, the kotatsu table was introduced to insulate heat in the body at a lower cost.
The kotatsu represents the heart of the Japanese home in winter and is an important element of Japanese culture. Family members gather together and enjoy watching TV, playing games and having long conversations in the evening under the warmth of the table.
Most people may think that these tables are not effective and can only warm the lower part of the body. Its heat could easily go through kimonos and trap heat throughout the body.
Although we usually find its purpose as a dining table to keep families warm while eating. In addition, as long as you want to keep warm under the kotatsu.
Some people even take a nap or sleep under the kotatsu to keep warm despite the uneven insulation.
The kotatsu table proves to be not only cost-saving, but also very versatile. Families can use the Kotatsu not only in the winter to keep warm.
They can also use it in the summer by removing the blanket and unplugging the electric heater. Finally, take out the warm functionality of the kotatsu.