Life in an old Japanese house Vol.2: All about Tatami Part 2

If you look through real estate listings in Japan, you’ll soon notice the tendency to list the size of rooms by the number of tatami mats. For people new to Japan, this measurement system is confusing, but once you get a grasp of the size of a 4.5 tatami room versus a 6 tatami mat, it can be much clearer than writing the number of square meters. Some shady real estate agents will try to put the number of square meters in small print and use smaller tatami mats in the room so they can trick customers into thinking the room is a bit bigger. 

Even when purchasing carpet or paint, you’ll find the number of tatami mats listed to give people a good approximation of the coverage. The more you live here, the more you’ll find this measurement cropping up here and there. That said, it can be a rather troublesome system as it is not exactly reliable.


Pictured on the left is a 6 tatami mat room and on the right is part of a 12 mat room.

The largest amongst the standard sizes of tatami is the ‘Kyo ma’ or ‘Honken ma’ mat which is chiefly found in the Kansai area especially Kyoto. It’s proportions are 191 by 95.5 cm. Coming in a close second is the ‘Aki ma’ or ‘Rokuichi ma’ which is found in Hiroshima and other parts along the Setouchi seaside. It is 185 by 92.5 cm.  After that is the ‘Chukyo ma’ or ‘Saburoku ma’ mats which have the same 3 by 6 proportions as commonly used building materials plywood and drywall. It comes in at 182 by 91 cm. ‘Edo ma’ or ‘Gohachi ma’ is used throughout the country especially Tokyo and the greater Kanto area and measures 176 by 88 cm. During the Japanese Economic Miracle from 1955 to 1973 the ‘Danchi ma’ or ‘Goroku ma’ were widely used in public housing and are quite small at 170 by 85 cm. The proportions of all these tatami are 2 to 1 but the Ryukyu mat from Okinawa is the one type which has equal proportions of 88 by 88 cm. These mats are often found placed in modern homes directly on the wood flooring.


These various standard sizes of tatami that I’ve covered in this article are all a rough approximation with the actual size of each mat varying slightly. In fact, if you check the back of the mat you’ll find information for each mat and it’s precise position in the room. Tatami fit together like puzzle pieces and if it’s not in the right spot then you won’t be able to put them in place. It might seem counterproductive for each tatami to be different, but it’s due to the fact that homes are not planned around tatami but rather the amount of land available to build on. Therefore once the floor plan is decided for a room, then the size of tatami is calculated to fit the blueprint. Since land is never perfectly level or square, the foundation and floor are built incorporating those irregularities. Tatami craftsmen are highly skilled at calculating precisely the size and shape of the room to create mats that perfectly fit in their proper place. 

There is a common saying in Japan related to tatami mats, ‘Man needs only half a mat to stand, only one mat to sleep, and even a king only needs 2 and half cups of rice a day.’ It means every man needs only a small amount of space to live, and no matter how great a status and power he may yield, this does not change. Therefore do not seek more than you truly need and it’s important to be satisfied with what one has. Compared to the Japanese of long ago, people have grown bigger and therefore one tatami mat wouldn’t suffice for sleeping on. Before futons were invented, tatami were used as mattresses for the aristocrats. It is for that reason that mats were made to be big enough for one person to lay down on thereby leading to this saying becoming popularized. Beyond being a mattress, tatami were also used as carpet for the mansions of the wealthy. During the Heian Period (794-1185), the thickness, size and color of the mat were strictly based on one’s social status. As time passed, tatami mats slowly became used by the samurai class and then eventually the townspeople. Tatami is also closely connected to the Japanese tea ceremony. In the Muromachi Period (1336-1573), the size of tea rooms was fixed at 4 and a half mats. The architectural style Sukiya-zukuri which designs buildings around furthering the enjoyment of tea, was what popularized the concept of using the number of tatami mats in considering a room’s floor plan which continues to this day.  There is also the ‘tokonoma’, a space synonymous with Japanese rooms which was developed along with tatami mats. For those who wish to deepen their understanding of Japanese culture, it doesn’t hurt to learn more about tatami mats.

By the way, those involved in the martial arts including karate and judo are familiar with a kind of tatami mat used there, but these mats are in fact not actual tatami. I hope you’ll have a chance to  stay somewhere with real tatami some day!