This article is about the Japanese flooring. For the Japanese armour component, seeTatami-dō. For the film, seeTatami (film).
Tatami (畳) are softmats used as flooring material in traditionalJapanese-stylerooms. They are made in standard sizes, twice as long as wide, about 0.9 by 1.8 metres (3 by 6 ft), depending on the region. In martial arts, tatami are used for training in adojo and for competition.[1]
Tatami are covered with aweft-faced weave ofsoft rush (藺草,igusa) on a warp of hemp or weaker cotton. There are four warps per weftshed, two at each end (or sometimes two per shed, one at each end, to reduce cost). Thedoko (core) is traditionally made from sewn-together rice straw, but contemporary tatami sometimes havecompressed wood chip boards orextruded polystyrene foam in their cores instead or as well. The long sides are usually edged (縁,heri) withbrocade or plain cloth, although some tatami have no edging.[2][3]
The termtatami is derived from the verbtatamu (畳む), meaning 'to fold' or 'to pile'. This indicates that the early tatami were thin and could be folded up when not used or piled in layers.[4]
Tatami were originally a luxury item for the nobility. The lower classes had mat-covered earthen floors.[5] During theHeian period, when theshinden-zukuri architectural style of aristocratic residences was consummated, the flooring of shinden-zukuri palatial rooms was mainly wooden, and tatami were used as seating only for the highest aristocrats.[6]
Before the mid-16th century, the ruling nobility and samurai slept on tatami or woven mats calledgoza (茣蓙), while commoners used straw mats or loose straw for bedding.[7] Tatami were gradually popularized and reached the homes of commoners toward the end of the 17th century.[8]
Houses built in Japan today often have few or no tatami-floored rooms. Having just one such room is common. Rooms having tatami flooring and other such traditional architectural features are referred to asnihonma orwashitsu, "Japanese-style rooms".
Green tatami in a museum model of theSaikū palace in ~the 9th century
Tatami can be categorized by their size, correlated to their place of origin:
Kyōma (京間) tatami: 1.91 by 0.955 m (6 ft 3.2 in by 3 ft 1.6 in), originated fromKyoto
Chūkyōma (中京間) tatami: 1.82 by 0.91 m (6 ft 0 in by 3 ft 0 in), also calledAinoma (合の間,lit. "in-between" size) tatami, originated fromNagoya
Edoma (江戸間) tatami: 1.76 by 0.88 m (5 ft 9 in by 2 ft 11 in), also calledKantōma (関東間) tatami, originated fromTokyo
In terms oftraditional Japanese length units, a tatami is 1 by 0.5ken, or equivalently 6 by 3shaku. The length of these units varies regionally, which led different regions to develop separate tatami size conventions. Oneshaku is approximately the same length as one foot in the British-American measurement system. As for thickness, 5.5 cm (2.2 in) is average forKyōma tatami, while 6.0 cm (2.4 in) is the norm forEdoma tatami.[6]
A half mat is called ahanjō (半畳), and a mat of three-quarter length is called adaimedatami (大目畳 or台目畳), which is used in tea-ceremony rooms (chashitsu).[4]
In Japan, the size of a room is usually measured in relation to the size of tatami mats (-畳,-jō), about 1.653 m2 (17.79 sq ft) for a standard Nagoya-size tatami. Alternatively, in terms oftraditional Japanese area units, room area (and especially house floor area) is measured in terms oftsubo, where onetsubo is the area of two tatami mats (forming a square); formally 1 by 1ken or about 3.306 m2 (35.59 sq ft).
Some common room sizes in the Nagoya region are:
4+1⁄2mats = 9shaku × 9shaku ≈ 2.73 m × 2.73 m (8 ft 11 in × 8 ft 11 in)
6mats = 12shaku × 9shaku ≈ 3.64 m × 2.73 m (11.9 ft × 9.0 ft)
8mats = 12shaku × 12shaku ≈ 3.64 m × 3.64 m (11.9 ft × 11.9 ft)
Another format is theRyūkyū (琉球) tatami, originating from theRyūkyū Islands, which are square and can have various measurements.[9]Ryūkyū tatami do not have borders, and have become popular in modern times for their simplicity.[10]
There are rules concerning the number of tatami mats and their layout in a room. In theEdo period, "auspicious" (祝儀敷き,shūgijiki) and "inauspicious" (不祝儀敷き,fushūgijiki) tatami arrangements were distinctly differentiated, with tatami rearranged depending on the occasion. In modern practice, the "auspicious" layout is normally used. In this arrangement, the junctions of the tatami form a "T" shape; in the "inauspicious" arrangement, the tatami are in a grid pattern wherein the junctions form a "+" shape.[6] An auspicious tiling often requires the use of1⁄2 mats to tile a room.[11] It isNP-complete to determine whether a large room has an auspicious arrangement using only full mats.[12]
An inauspicious layout was used to avoid bad fortune at inauspicious events such as funerals. Now it is widely associated with bad luck and itself avoided.[13]
Some auspicious layouts from the early 1800s (Edo Period)
One possible auspicious layout of a4+1⁄2 mat room
Half mat
Full mat
Typical layout of a4+1⁄2 mat tea room in the cold season, when the hearth built into the floor is in use. The room has atokonoma andmizuya dōko
Room with tatami flooring in an inauspicious layout and paper doors (shōji)
^Erickson, Alejandro;Ruskey, Frank; Schurch, Mark; Woodcock, Jennifer (2010). "Auspicious tatami mat arrangements". In Thai, My T.; Sahni, Sartaj (eds.).Computing and Combinatorics, 16th Annual International Conference, COCOON 2010, Nha Trang, Vietnam, July 19-21, 2010. Proceedings. Lecture Notes in Computer Science. Vol. 6196. Springer. pp. 288–297.arXiv:1103.3309.doi:10.1007/978-3-642-14031-0_32.MR2720105.
^Erickson, Alejandro;Ruskey, Frank (2013). "Domino tatami covering is NP-complete". In Lecroq, Thierry; Mouchard, Laurent (eds.).Combinatorial Algorithms: 24th International Workshop, IWOCA 2013, Rouen, France, July 10-12, 2013, Revised Selected Papers. Lecture Notes in Computer Science. Vol. 8288. Heidelberg: Springer. pp. 140–149.arXiv:1305.6669.doi:10.1007/978-3-642-45278-9_13.MR3162068.S2CID12738241.
^Kalland, Arne (April 1999). "Houses, People and Good Fortune: Geomancy and Vernacular Architecture in Japan".Worldviews.3 (1):33–50.doi:10.1163/156853599X00036.JSTOR43809122.