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【Basic knowledge of real estate Vol.1】Notation and meaning of 1R, 1K, 1DK and 1LDK

  • Japanese real estate expertise
【Basic knowledge of real estate Vol.1】Notation and meaning of 1R, 1K, 1DK and 1LDK

When you as a foreign investor search for Japanese real estate on the Internet, you see many advertisements.

At first, I think you didn’t understand the notations and explanations of the floor plan that you were not familiar with. Here are the questions that I, as the writer of this article and who is also a sales staff of CLEARTH LIFE, received from those who are considering real estate investment in Japan for the first time;

“When I checked on the Internet, there are ‘1R and 1K’ investments in Japan. What is the meaning of 1R and 1K??”
“What is the difference between 1DK and 1LDK?”

I would like to explain the Japanese floor plan notation “1R”, “1K”, “1DK” and “1LDK” this time.


“Isn’t the room itself that much different between 1R and 1K…?”

Let’s take a look at the above floor plans.
Generally, the points to distinguish are kitchen and room(bedroom).
1R read as “One-room” which the kitchen space is not divided by a door, also known as a studio type room. The area of the room is between 10sqm and 25sqm with a unit-bath(bathtub/shower, wash basin and toilet are built-in; see the below right photo). The kitchen is located inside the room. Such apartments were mainstream in Japan in the 1970s and 1980s. For this reason, the apartments currently being marketed are characterized by being old.

③1R トイレ

 *Reference photo by CLEARTH RENT

Advantages of 1R are;
・Since the room area itself is not big, the investment cost can be lower than 1K.
・Rent is relatively cheap for tenant.
・Also suitable for those with few luggage.

Disadvantages of 1R are;

・Since it is connected to the room immediately from the entrance, privacy is not protected from visitors.
・There is normally a built-in type unit-bath, so it is not for people who concern hygiene.
・Since there is a kitchen in the room, the smell of cooking remains.
・Because home appliances such as refrigerator is in the same room, it may be a source of worry for people who are sensitive to sound.
・Not suitable for those who cook a lot because the kitchen is small.

With the development of the Japanese economy and the increasing number of people who are considering a better living environment, there are also “1R” type apartments with an area of about 30sqm supplied.

The “1K” type room also has a layout with one room and kitchen. The difference is that there is a partition such as a door between the kitchen and the room. The area of the room is about 20sqm to 30sqm, and you can frequently find apartments with separate toilet and bathroom as well. Japan’s rapid economic growth from the 1950s to 1970s has led to an increase in people seeking better living since the 1990s. 1K type apartments for single living which provide rich living have become mainstream since this time. For this reason, many 1K type apartments are relatively young compare to 1R type.

④1K トイレ

*Reference photo by CLEARTH LIFE

Advantages of 1K are;
・There is not a room immediately after entering the entrance, so privacy is protected.
・Since there is a door between the kitchen and the room, the smell of cooking does not stay in the room.
・Toilet and bathroom are outside the room, so it is hard to be bothered by daily sounds such as ventilation fan and running water.
・Relatively spacious closet is provided, so the room can be used spaciously. (Room is bigger than 1R.)
The 1K type apartment is very popular with singles and women who want to use a spacious room.

Disadvantage  of 1K is;
・High value because of relatively bigger room and younger building age. Therefore, the selling price and rent are transacted higher than 1R.

“1LDK” is generally about 30sqm to 40sqm in size or sometimes up to 45sqm. “L” represents the Living room and “D” represents the Dining room.


*Reference photo by CLEARTH LIFE

There is another notation which is “1DK”. “DK” represents the Dining and Kitchen. The difference between 1DK and 1LDK is the size of the room with the kitchen.
Area of Dining and Kitchen(DK) needs bigger than 4.5 jo(帖) which is about 6.98sqm.
On the other hand, area of Living, Dining and Kitchen(LDK) needs bigger than 8 jo(帖) which is about 12.4sqm.

Advantages of 1LDK are as follows while having the advantages of 1K type;
・Since the bedroom and LDK area are separated, it is the perfect layout for smokers and those who do not want to bring the smell from the LDK, etc. into the bedroom.
・Even if there is a sudden visitor, it is easy to live because you can secure a private space just by closing the door between LDK space and bedroom.
・The room is spacious, so you can choose your favorite furniture to create a comfortable environment.

 Disadvantages  of 1LDK are;
・It may be a bit difficult for people who are not good at cleaning since the room is big.
・Utility bills are a bit expensive compare to smaller room.

Higher rent may be one of the disadvantages from the tenant side, however as the room becomes bigger, people with good occupations that match the rent will consider and actually move-in. These people tend to have a stable income and have a relatively low risk of unpaid rent which gives one of the advantages for the owners.


Of course, “1R”, “1K”, “1DK” or “1LDK” has its advantages and disadvantages, so it is not always possible to tell which room type is the best for everyone.

We, CLEARTH LIFE were founded in 1984 and have developed apartments specializing in the center of Tokyo. We have a lot of experience not only in buying and selling, but also in rental management and building management.

If you have any questions about Japanese real estate, please do not hesitate to contact us!


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