Kang Bed-stove - History

History

The Kang is said to be derived from the concept of a heated bed floor called a 'huoqiang' found in China in the Neolithic period, according to analysis of archeological excavations of building remains in Banpo Xi'an. However, archeleogical sites in Shenyang, Liaoning, show humans using the heated bed floor as early as 7,200 years ago. The bed at this excavation is made of 10 cm pounded clay on the floor. The bed was heated by 'zhidi' which is simply the process of placing an open fire on the bed floor and clearing the ashes before sleeping. It is mentioned by Tang poet Meng Jiao in his poem titled Handi Baixing Yin. 'No fuel to heat the floor to sleep, standing and crying with cold at midnight instead'. In the excavated example the repeated burning is believed to have turned the bed surface hard and moisture resistant.

The first known type of heated platform appeared in modern-day Northeast of China and used a single flue system of Korean origin. An example of this type of heated platform was unearthed in 1st-century building remains in the Heilongjiang Province. Its single flue is 'L' shaped, built from adobe and cobblestones and covered with stone slabs.

Heated walls with a double flue system was found in a 4th century ancient palace building in the Jilin Province. It has an 'L' shaped adobe bench with a double flue system. It is structurally more complex than a single flue system and has functionality similar to a Kang.

The word Kang means 'to dry', first documented in the Chinese dictionary in AD121. The earliest Kang remains have been discovered at Ninghai, Heilongjing Province in the Longquanfu Palace (699-926) of Balhae origin.

The kang may have evolved to its bed design from earlier developments due to ongoing cultural changes during the Southern and Northern Dynasties, as high furniture and chairs came to be prevalent, over the earlier style of floor-sitting and low-lying furniture in Chinese culture.

Literary evidence from the Shui Jing Zhu also gives evidence of heated floors by the Northern Wei Dynasty, though it was not explicitly named a dikang:

In Guanji Temple, there is a grand lecture hall. It is very high and wide to accommodate a thousand monks. The platform of the hall was constructed with stones arranged as a network of channels, and the floor was finished with a coat of clay. Fires are set at outdoor openings at the four sides of the platform, while the heat flows inwards warming the entire hall. The construction was established by a benefactor (or benefactors) to enable the monks to study in cold winters. —Li Daoyuan, Shui Jing Zhu

Outside China, the concept of a "masonry heater", a large stove made of brick or other masonry keeping a house warm for a long time, has been used in various forms throughout northern and eastern Europe. In particular, Russians have traditionally used a similar sort of stove/bed, known as the Russian oven (Russian: Русская печь); it is unknown whether this was introduced from the East during the period of the "Tatar yoke".