Understanding Japanese Real Estate Measurement Units: A Comprehensive Guide

When navigating the Japanese real estate market, it’s essential to familiarize yourself with various measurement units that describe property areas. These units, such as 坪 (Tsubo), 平米 (Heibei), ㎡ (Square Meter), 畳 (Jo), and others, are commonly used in property advertisements, whether you’re looking to buy, sell, or rent a property in Japan. This guide will explore the most widely used units, helping you understand what they mean and how they are applied in real estate contexts.

坪 (Tsubo)

“Tsubo” is a traditional Japanese unit of area which was in use before Japan adopted the metric system. One Tsubo is equivalent to approximately 3.3 square meters. This unit is often employed to describe land area or office space in the real estate industry.

Price Per Tsubo

In Japan, the unit price per Tsubo is frequently used to express the cost of property, rent, or construction. Here’s how it’s applied:

  • Rent per Tsubo: Calculated by dividing the total rent and common service fees by the area in Tsubo.
  • Property price per Tsubo: Determined by dividing the property’s sale price by its area in Tsubo.
  • Construction cost per Tsubo: This reflects the building cost divided by the total floor area measured in Tsubo.

平米 (Heibei) and ㎡ (Square Meter)

These units are based on the metric system and represent the area of a square that is one meter on each side. Heibei and Square Meters are the standard units for measuring land, building areas, and total floor space.

According to the ‘Enforcement Rules for Fair Competition Codes Concerning Indication of Real Estate‘ set by the ‘Real Estate Fair Trade Council of Federation,’ it’s mandatory to use the metric system when indicating the area of land or building floor space in advertisements. This makes Heibei and Square Meters the standard units you’ll see in most real estate listings, whether online or in brochures.

畳 (Jo)

“Jo” is a unit of area that corresponds to the size of a single tatami mat, traditionally used to measure room sizes in Japanese homes. The size of a tatami mat varies by region as can be seen below:

  • Kyoma (Kansai region): Approximately 1.82 square meters
  • Edoma (Kanto region): Approximately 1.55 square meters
  • Danchima (used in apartments): Approximately 1.44 square meters
 

The ‘Enforcement Rules for Fair Competition Codes Concerning Indication of Real Estate’ stipulate that one Jo should be at least 1.62 square meters.

帖 (Jo)

This term is also used to denote the size of a room, similar to 畳 (Jo), but it can apply to rooms with different types of flooring, such as wooden or carpeted rooms. Like its counterpart, the minimum area for one Jo is set at 1.62 square meters.

It’s important to note that both 畳 (Jo) and 帖 (Jo) are general indicators of room size rather than exact measurements. Before signing any real estate contracts, it’s advisable to verify the area in square meters to avoid misunderstandings.

Wall-Core Area vs. Inner Area

When assessing floor space, there are two primary ways to represent the area: Wall-Core Area and Inner Area.

  • Wall-Core Area: This measurement includes the thickness of walls and pillars, typically making the area appear larger than the actual usable space. It’s often used in building certification applications, property registration for detached houses, and mortgage deductions for detached homes.

  • Inner Area: This measurement reflects the usable space within the walls and pillars. It’s commonly used for registering building unit ownership, such as condominiums, and for mortgage loan deductions related to these units.

The Wall-Core Area tends to be larger than the Inner Area due to the inclusion of half the wall thickness. The difference in size between these two measurements can vary depending on the building’s structure and wall thickness. For instance, the difference is more pronounced in smaller units, with studio apartments typically showing about an 11% difference, while family-sized apartments have a roughly 6% difference.

In real estate advertisements, there is no strict rule regarding whether to use Wall-Core Area or Inner Area. However, newly built detached houses and condominiums usually list Wall-Core Area, whereas pre-owned condominiums often use Inner Area. When reviewing property drawings, it’s crucial to confirm which area measurement is being used.

Summary

Navigating the various units used in Japanese real estate advertisements, such as 坪 (Tsubo), m2, and 畳 (Jo), can be challenging. However, remembering that 1 坪 (Tsubo) equals approximately 3.3 m2 or 2 畳 (Jo) can be helpful when interpreting these measurements. As you view more properties, you’ll develop a better sense of housing sizes.

The ideal home size depends on factors like family size and lifestyle preferences. Room size, along with ceiling height, significantly impacts the comfort and overall impression of your living space. Take the time to explore different properties to find the perfect residence that meets your needs and expectations.

Article by Christophe Audisio

Sources:

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