Floor-Area Ratio (FAR) and Building Coverage Ratio (BCR) in Japan

Poste date: Thursday, April 20, 2017

Land Use Zones restricts the use of buildings in each categorized zone; it also controls volume and height of buildings by Floor-Area Ratio (FAR) and Building Coverage Ratio (BCR) in each zone.
What size and height of the building you can build depends on FAR and BCR of the land property and this also influences the property price.

As FAR and BCR are described in the property information provided by the real estate company, it is recommended to understand beforehand when you plan to purchase a real estate property.

What is Building Coverage Ratio (BCR)?

The ratio of the Building area divided by the land (site) area. Building area means the floor space of a building when looking down at it from the sky.

Depending on the Land Use Zone category it is regulated within 30% - 80%, and a building has to be constructed within the specified maximum BCR ratio in the zone.

For example; in case of a Land area of 100㎡ with a BCR at 50%, a building with the maximum (Building area) of 50㎡ can be constructed.

What is Floor-Area Ratio (FAR)?

The ratio of Total floor area divided by Land (site) area. Total floor area means the total of all the floor space in a building.

Depending on the Land Use Zone category, it is regulated in the range of 50% - 1,300%.

For example; in case of a Land area of 100㎡ and a FAR of 300%, a building with maximum (Total floor area) of 300㎡ can be constructed.

The Floor-area Ratio and Building Coverage Ratio in each Land Use Zone

Under these following specific cases, Building Coverage Ratio (BCR) and Floor-Area Ratio (FAR) may be relaxed or additional restrictions may apply.

Relaxation of Building Coverage Ratio

● Corner land: A corner plot of land (specified by the government) is allowed to add 10% to the maximum BCR,
when additional specified conditions are satisfied such as the width and angle of the adjacent road and the length
of contact with the adjacent land. ＊Please consult the local government office.

● In case of a fireproof building: A fireproof building in the fire protection zone is allowed to add 10% to the
maximum BCR.

Additional limits to Floor Area Ratio

● Limit to FAR depending on the width of the frontal road:

When the width of the frontal road is less than 12m, the lower ratio shall be adopted between the specified FAR
and the ratio by the following calculations:
*　In case of Residential Land Use Zones: The width of the frontal road (m) x 4/10
*　In case of Land Use Zones other than Residential: The width of the frontal road (m) x 6/10.

Relaxation of Floor Area Ratio

● If a case is specially allowed by the administrative agency concerned

● In case of apartment buildings the elevator hall and stairs for public use shall not be calculated in FAR

● In the case of underground floors being used for residential use

● In case the land (site) has any other exceptional rules adopted.