ArticleslgStudy

science

Tatami

Tatami is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Tatami rather than just read about it. In short: Tatami (畳) are soft mats used as flooring material in traditional Japanese-style rooms. 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.

Tatami — main illustration
Tatami — illustration

Key takeaways

  • Tatami belongs to science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Tatami to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Tatami from memory before moving on to harder problems.

Reference excerpt

Tatami (畳) are soft mats used as flooring material in traditional Japanese-style rooms. 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 a dojo and for competition. Tatami are covered with a weft-faced weave of soft rush (藺草, igusa) on a warp of hemp or weaker cotton. There are four warps per weft shed, two at each end (or sometimes two per shed, one at each end, to reduce cost). The doko (core) is traditionally made from sewn-together rice straw, but contemporary tatami sometimes have compressed wood chip boards or extruded polystyrene foam in their cores instead or as well. The long sides are usually edged (縁, heri) with brocade or plain cloth, although some tatami have no edging. Tatami have also traditionally been used for tameshigiri, the Japanese art of target test cutting.

History The term tatami is derived from the verb tatamu (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. Tatami were originally a luxury item for the nobility. The lower classes had mat-covered earthen floors. During the Heian period, when the shinden-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. In the Kamakura period, there arose the shoin-zukuri architectural style of residence for the samurai and priests who had gained power. This architectural style reached its peak of development in the Muromachi period, when tatami gradually came to be spread over whole rooms, beginning with small rooms. Floors completely covered with tatami came to be known as zashiki (座敷), lit. 'spread out for sitting', and rules concerning seating and etiquette determined the arrangement of the tatami in the rooms. Before the mid-16th century, the ruling nobility and samurai slept on tatami or woven mats called goza (茣蓙), while commoners used straw mats or loose straw for bedding. Tatami were gradually popularized and reached the homes of commoners toward the end of the 17th century. 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 as nihonma or washitsu, "Japanese-style rooms".

Size 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 from Kyoto Chūkyōma (中京間) tatami: 1.82 by 0.91 m (6 ft 0 in by 3 ft 0 in), also called Ainoma (合の間; lit. "in-between" size) tatami, originated from Nagoya Edoma (江戸間) tatami: 1.76 by 0.88 m (5 ft 9 in by 2 ft 11 in), also called Kantōma (関東間) tatami, originated from Tokyo In terms of traditional Japanese length units, a tatami is 1 by 0.5 ken, or equivalently 6 by 3 shaku. The length of these units varies regionally, which led different regions to develop separate tatami size conventions. One shaku 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 for Kyōma tatami, while 6.0 cm (2.4 in) is the norm for Edoma tatami. A half mat is called a hanjō (半畳), and a mat of three-quarter length is called a daimedatami (大目畳 or 台目畳), which is used in tea-ceremony rooms (chashitsu). 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 of traditional Japanese area units, room area (and especially house floor area) is measured in terms of tsubo, where one tsubo is the area of two tatami mats (forming a square); formally 1 by 1 ken or about 3.306 m2 (35.59 sq ft). Some common room sizes in the Nagoya region are:

4+1⁄2 mats = 9 shaku × 9 shaku ≈ 2.73 m × 2.73 m (8 ft 11 in × 8 ft 11 in) 6 mats = 12 shaku × 9 shaku ≈ 3.64 m × 2.73 m (11.9 ft × 9.0 ft) 8 mats = 12 shaku × 12 shaku ≈ 3.64 m × 3.64 m (11.9 ft × 11.9 ft) Shops were traditionally designed to be 5+1⁄2 mats, and Japanese tea rooms are frequently 4+1⁄2 mats. Another format is the Ryūkyū (琉球) tatami, originating from the Ryūkyū Islands, which are square and can have various measurements. Ryūkyū tatami do not have borders, and have become popular in modern times for their simplicity.

Layout There are rules concerning the number of tatami mats and their layout in a room. In the Edo 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. An auspicious tiling often requires the use of 1⁄2 mats to tile a room. It is NP-complete to determine whether a large room has an auspicious arrangement using only full mats. 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.

See also Higashiyama Bunka in Muromachi period Petate Tameshigiri

References

External links Media related to Tatami at Wikimedia Commons

Illustrations

Tatami: Tatami mat in Enkō-ji
Tatami mat in Enkō-ji
Tatami illustration
Tatami illustration
Tatami illustration
Tatami illustration

Worked examples

Example 1 — a first encounter with Tatami

Start with the simplest possible case. Write down what Tatami claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Tatami before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Tatami ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Tatami

In research
Tatami appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Tatami in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Tatami is common in secondary-school and first-year university syllabi. It links to neighbouring topics Interior design, Japanese architectural features, Japanese home, so understanding it makes those chapters shorter.
In everyday life
Look for Tatami outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Tatami” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Tatami in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Tatami means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Tatami out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Tatami in simple terms?

Tatami (畳) are soft mats used as flooring material in traditional Japanese-style rooms. 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.

Why does Tatami matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Tatami?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Tatami.

Tags

  • Interior design
  • Japanese architectural features
  • Japanese home
  • Japanese martial arts equipment
  • Japanese rugs and carpets
  • Straw products
  • Units of area

Keep exploring