Example: Change of Use

Example: Change of Use

(Changing the use of a residential building with two floors or less and a total floor area of less than 200㎡ to an inn)

When changing the use of a building, the provisions on building coverage ratio, floor area ratio, and structural durability do not apply, but the restrictions of the zoning district and the provisions on fire prevention and evacuation apply depending on the intended use and scale of the change. 
When changing the use to a specified building with a total floor area of more than 100 square meters, a building permit application is required. 

Evacuation Regulations 

• Emergency lighting is required in guest rooms. 
  
• Although smoke ventilation equipment is required in guestrooms, etc., renovation is not necessary if the existing windows and other openings are effective for smoke ventilation. 

⇒The use can be changed if emergency lighting and windows are installed. 

Procedural Rules 

• In the case of a change of use with a floor area of more than 100 ㎡, an application for building permit is required. However, if the use is similar, no application is required. 
• For changes in use that require a building permit, it is necessary to notify the District Surveyor of the completion of construction. 
  

Collective Regulations 

• The building-to-land ratio and floor-area ratio are not applied retroactively. 
• Height regulations (oblique lines on roads, oblique lines on adjacent land, oblique lines on the north side, height districts) are not applied retroactively. 
• Restrictions on zoning are not applied retroactively. 

Fire Prevention Regulations 

• Fire prevention regulations are not applied retroactively to the existing part. 

⇒ Fire prevention regulations do not apply to buildings less than 200 m² with two or fewer floors. 

Other Laws and Regulations 
In addition to the Building Standards Law, other laws and regulations such as permits and approvals may be required for changes in use. 
Major Relevant Regulations 
(Fire Service Act) 

• In the case of Kyo-Machiya houses larger than a certain size, evacuation guiding lights and fire extinguishers must be installed. 

(Ryokan Business Law) 
The following may be required depending on the size of the building:

• Installation of a front desk
• Limits on the floor area of guest rooms
• Installation of bathrooms
• Installation of washrooms  
• Installation of lavatories. 

Notes:
The regulations for fire-prevention zones/quasi-fire-prevention zones and structural durability provisions do not apply retroactively, but in order to make buildings safe and secure, you are advised to make the building fireproof and earthquake-proof.