炬燵
   HOME

TheInfoList



OR:

A is a low, wooden table frame covered by a ''
futon A is a traditional Japanese style of bedding. A complete futon set consists of a and a . Both elements of a futon bedding set are pliable enough to be folded and stored away in a large during the day. This allows a room to serve as a bedro ...
'', or heavy
blanket A blanket is a swath of soft textile, cloth large enough either to cover or to enfold most of the user's body and thick enough to keep the body warm by trapping radiant body heat that otherwise would be lost through Thermal conduction, condu ...
, upon which a table top sits. Underneath is a heat source, formerly a charcoal
brazier A brazier () is a container used to burn charcoal or other solid fuel for cooking, heating or rituals. It often takes the form of a metal box or bowl with feet, but in some places it is made of terracotta. Its elevation helps circulate air, feed ...
but now
electric Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...
, often built into the table itself. ''Kotatsu'' are used almost exclusively in Japan, although similar devices for the same purpose of heating are used elsewhere, e.g. the Spanish ''brasero'' or Iranian '' korsi''.


History

The history of the ''kotatsu'' begins in the
Muromachi period The , also known as the , is a division of Japanese history running from approximately 1336 to 1573. The period marks the governance of the Muromachi or Ashikaga shogunate ( or ), which was officially established in 1338 by the first Muromachi ...
or Ashikaga shogunate during the fourteenth century. Its origins begin with the Japanese cooking
hearth A hearth () is the place in a home where a fire is or was traditionally kept for home heating and for cooking, usually constituted by a horizontal hearthstone and often enclosed to varying degrees by any combination of reredos (a low, partial ...
, known as the '' irori''. Charcoal was the primary method of cooking and heating in the traditional Japanese household and was used to heat the ''irori''. By the fourteenth century in Japan, a seating platform was introduced to the ''irori'' and its cooking function became separated from its seating function. On top of the wooden platform a quilt was placed, known as an ''oki'' that trapped and localized the heat of the charcoal burner. This early ancestor to the modern ''kotatsu'' was called a ''hori-gotatsu''. The word ''hori-gotatsu'' () is derived from the
kanji are logographic Chinese characters, adapted from Chinese family of scripts, Chinese script, used in the writing of Japanese language, Japanese. They were made a major part of the Japanese writing system during the time of Old Japanese and are ...
(hori) meaning ditch, digging, (ko) meaning torch or fire, and (tatsu) meaning foot warmer. The formation of the ''hori-gotatsu'' was slightly changed in the
Edo period The , also known as the , is the period between 1600 or 1603 and 1868 in the history of Japan, when the country was under the rule of the Tokugawa shogunate and some 300 regional ''daimyo'', or feudal lords. Emerging from the chaos of the Sengok ...
during the seventeenth century. These changes consisted of the floor around the ''irori'' being dug-out into the ground in a square shape. The wooden platform was placed around this, making a hearth. Then the blanket was placed on top of the platform again, where one could sit with legs underneath to stay warm. The moveable ''kotatsu'' was created later, originating from the concept of ''hori-gotatsu''. This ''kotatsu'' came about with the popular use of ''
tatami are soft mats used as flooring material in traditional Japanese-style rooms. They are made in standard sizes, twice as long as wide, about , depending on the region. In martial arts, tatami are used for training in a dojo and for competition. ...
'' matting in Japanese homes. Instead of placing the charcoals in the ''irori'', they were placed in an earthen pot which was placed on the ''tatami'' making the ''kotatsu'' transportable. This more modern style ''kotatsu'' is known as the ''oki-gotatsu''. The word ''oki-gotatsu'' () is derived from the kanji (oki) meaning placement, meaning torch or fire, and meaning foot warmer. In the middle of the twentieth-century charcoal was replaced with electricity as a heating source. Instead of having the moveable earthen pot of charcoals beneath the ''kotatsu'', it was possible to attach an electric heating fixture directly to the frame of the ''kotatsu''. By 1997, the majority (approximately two-thirds) of Japanese homes had the modern ''irori'' and 81 percent had a ''kotatsu'', though they are warmed using electricity instead of glowing coals or charcoal. Thus, the ''kotatsu'' became completely mobile with electricity and became a common feature of Japanese homes during winter.


Types

There are two kinds of ''kotatsu'' used in Japan today, differing in the configuration and the type of heating: * Electric: The modern style of ''kotatsu'', , consists of a table with an electric heater attached to the underside of the table. This evolved from a clay pot with hot coals placed under a table. The ''kotatsu'' usually is set on a thin ''futon'', like a throw rug. A second, thicker blanket is placed over the ''kotatsu'' table, above which the tabletop is placed. The electric heater attached to the underside of the table heats the space under the comforter. * Charcoal: The more traditional type is a table placed over a recessed floor, . The pit is cut into the floor and is about 40 centimeters deep. A
charcoal Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, ca ...
heater is placed somewhere in the pit's floor, walls, or, as in the modern-style ''kotatsu'', attached to the table-frame. There are also pit-type ''kotatsu'' with an electric heater. File:Kotatsu.svg, Types of heating and layers of the ''kotatsu'' File:Japanese CoalBriquettes Mametan 02.jpg, coal briquettes mostly used in the early twentieth century


Use

In the twenty-first century, the ''kotatsu'' typically consists of the electric heater attached to the frame, which is no longer limited to wood, but may be made of plastic or other materials. Generally, a blanket (or ''shitagake'') is draped over the frame and heater and under the table-top. This first blanket is covered by a second heavier blanket, known as a (). A person sits on the floor or on '' zabuton'' cushions with their legs under the table and the blanket draped over the lower body. The ''kotatsu'' was designed when people most commonly wore traditional Japanese style clothes, where the heat would enter through the bottom of the robes and rise to exit around the neck, thus heating the entire body. Most Japanese housing is not insulated to the same degree as a Western domicile and does not have
central heating A central heating system provides warmth to a number of spaces within a building from one main source of heat. A central heating system has a Furnace (central heating), furnace that converts fuel or electricity to heat through processes. The he ...
, thus relying primarily on space heating. Heating is expensive because of the lack of insulation and the draftiness of housing. A ''kotatsu'' is a relatively inexpensive way to stay warm in the winter, as the futons trap the warm air. Families may choose to concentrate their activity in this one area of the house in order to save on energy costs. In the summer, the blanket may be removed, and the ''kotatsu'' used as a normal table. It is possible to sleep under a ''kotatsu'', although unless one is quite short, one's body will not be completely covered. This generally is considered acceptable for naps, but not for overnight sleeping for many reasons: one's body is not completely covered, yielding uneven heating; the table is low, so one may touch heating elements accidentally when moving while asleep, risking burns. Traditionally, children are told that they will catch a cold if they sleep under a ''kotatsu''. Pets, such as cats, frequently sleep under ''kotatsu'', however, and are small enough to fit completely underneath—comparable to cats who sleep on floor heating vents in Western countries (Japanese homes do not generally have floor heating vents). During the winter months in Japan, the ''kotatsu'' often is the center of domestic life. In the evening family members gather around the ''kotatsu'' to enjoy food, television, games, and conversation while keeping the lower half of their bodies warm. It has been said that "once under the ''kotatsu'', all of your worries slip away as a familiar warmth takes over and you become completely relaxed." Historically, were made of
bast fiber Bast fibre (also called phloem fibre or skin fibre) is plant fibre collected from the phloem (the "inner bark", sometimes called "skin") or bast surrounding the stem of certain dicotyledonous plants. Some of the economically important bast fibr ...
s. Later, cotton was introduced (1300s to 1700s, depending on region) and they were usually made of bast-filled quilts of recycled cotton, dyed with indigo and pieced from old garments in boroboro style. , for going under the , as a floor covering, were made the same way. In the 2010s, ''kotatsu-gake'' were often decorative and might be designed to match home décor.


Other countries

There are similar economical and often sociable systems to keep warm while sitting still in countries around the world. In Spain and Portugal, the ' is a small round table with a '' brasero'' heater (i.e. a
brazier A brazier () is a container used to burn charcoal or other solid fuel for cooking, heating or rituals. It often takes the form of a metal box or bowl with feet, but in some places it is made of terracotta. Its elevation helps circulate air, feed ...
) placed underneath. The Netherlands used to use a foot stove. During
World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
, British
Royal Engineers The Corps of Royal Engineers, usually called the Royal Engineers (RE), and commonly known as the ''Sappers'', is the engineering arm of the British Army. It provides military engineering and other technical support to the British Armed Forces ...
built 'Japanese footwarmers' in the trenches. The 18th-century traveler Lady Mary Wortley Montagu describes the similar '' tendour'' in her '' Turkish Embassy Letters''. Tajikistan and Afghanistan have the very similar ''sandali'', used even today in many traditional houses as a warm family eating place. Another similar item called the '' korsi'' is used likewise in
Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...
. In China and Korea,
underfloor heating Underfloor heating and cooling is a form of Heating, ventilation, and air conditioning, central heating and cooling that achieves indoor climate control for thermal comfort using hydronics, hydronic or electrical heating elements embedded in a fl ...
traditionally is used. The devices used in a similar fashion are, respectively, a Kang bed-stove and an ''
ondol (; , ; ) or ''gudeul'' (; ) in Korean traditional architecture is underfloor heating that uses direct heat transfer from wood smoke to heat the underside of a thick masonry floor. In modern usage, it refers to any type of underfloor heating, or ...
''. Romans used a
hypocaust A hypocaust () is a system of central heating in a building that produces and circulates hot air below the floor of a room, and may also warm the walls with a series of pipes through which the hot air passes. This air can warm the upper floors a ...
for
underfloor heating Underfloor heating and cooling is a form of Heating, ventilation, and air conditioning, central heating and cooling that achieves indoor climate control for thermal comfort using hydronics, hydronic or electrical heating elements embedded in a fl ...
.


See also

* '' Chabudai'', a short-legged table used in traditional Japanese homes * Electric blanket * ''
Hibachi The is a traditional Japanese heating device. It is a brazier which is a round, cylindrical, or box-shaped, open-topped container, made from or lined with a heatproof material and designed to hold burning charcoal. It is believed dates ...
'', a traditional Japanese heating device * Korsi *
Passive house Passive house () is a voluntary standard for energy efficiency in a building that reduces the building's carbon footprint. Conforming to these standards results in ultra-low energy buildings that require less energy for space heating or co ...


References


External links

* {{Authority control Heating Japanese architectural features Japanese home Portable furniture Tables (furniture)