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Site Rules & Related Laws and Regulations

Construction – Building (SSW 2) · 建設分野(2号・建築区分) · Written by Tokutei Pass based on the official study texts; not copied verbatim.

Construction Business Act (Contracts, Chief/Managing Engineers & Subcontracting Rules)

Under the Construction Business Act, construction contracts must be concluded on an equal footing in writing, signed or sealed, and exchanged by both parties. Minor construction work (other than general building work) with a contract price 'under 5 million yen (tax included)' can be undertaken without a construction business license.

A licensed construction contractor must assign a 'Chief Engineer (Shunin gijutsusha)' to every construction site regardless of contract amount to manage technical construction matters.

When a Specified Construction Contractor receiving a contract directly from the client concludes subcontracts totaling '45 million yen or more (70 million yen or more for general building work)', a 'Managing Engineer (Kanri gijutsusha)' must be assigned instead to supervise the entire project.

'Blanket subcontracting (Ikkatsu shitaukeoi / Marunage)'—passing an entire contracted project to another company—is completely prohibited in public works and prohibited in principle in private works.

Construction Business Act (Contracts, Chief/Managing Engineers & Subcontracting Rules)

Key points


  • Non-architectural-general work under 5 million yen (tax included) is minor construction work; contracts must be exchanged in writing.

  • Assign a 'Chief Engineer' to every site, or a 'Managing Engineer' when subcontracts total 45 million yen (70 million yen for general building) or more.

  • Blanket subcontracting (Marunage) is completely banned in public works and prohibited in principle in private works.
WordMeaning
Chief Engineer (Shunin gijutsusha)
Managing Engineer (Kanri gijutsusha)
Blanket subcontracting (Ikkatsu shitaukeoi / Marunage)

Labor Standards Act, Industrial Safety and Health Act & Workers' Compensation

Under the Labor Standards Act, a break of 'at least 60 minutes' is required when daily working hours exceed 8 hours (e.g., 8 hours 30 minutes); overtime or holiday work requires filing a 'Labor-Management Agreement (Article 36 Agreement)' with the Labor Standards Inspection Office and paying premium wages of '25% or more' for overtime and '35% or more' for statutory holidays.

Wages must be paid 'at least once a month, on a fixed date, in currency, directly to the worker, and in full'; workers employed continuously for 6 months with at least 80% attendance receive '10 working days' of paid annual leave.

For construction sites, the prime contractor enrolls in Workers' Compensation Insurance as a whole, covering subcontractor workers as well; a Worker Casualty Report for injuries causing fewer than 4 days of absence (e.g., 3 days) is compiled 'every 3 months and submitted by the end of the following month'.

Under the Industrial Safety and Health Act, sites with '50 or more' mixed workers require an 'Overall Safety and Health Controller'; safety training is required upon hiring/task change and for new foremen; working floors and guardrails are required at heights of 2 m or more; and an 'Operations Chief' must be appointed from skill training graduates for hanging scaffolds, cantilevered scaffolds, or scaffolds 5 m or higher.

Key points


  • Provide a ≥ 60-minute break when working over 8 hours; overtime premium is ≥ 25% and statutory holiday premium is ≥ 35% (with an Article 36 Agreement); 6 months service (≥ 80% attendance) grants 10 days paid leave.

  • Workers' Comp Insurance is covered collectively by the prime contractor; 3-day absence casualty reports are submitted quarterly by the end of the next month.

  • Appoint an 'Overall Safety and Health Controller' for ≥ 50 mixed workers, an 'Operations Chief' for hanging/cantilevered/≥ 5 m scaffolds, and working floors at heights ≥ 2 m.
WordMeaning
Article 36 Labor-Management Agreement (Sanroku kyoutei)
Overall Safety and Health Controller (Toukatsu anzen eisei sekininsha)
Worker Casualty Report (Roudousha shishoubyou houkoku)

Building Standards Act (Coverage Ratio, Floor Area Ratio, Height Limits) & Road Permits

Under the Building Standards Act, the maximum ratio of building area (horizontal projection area viewed from above) to site area is the 'building coverage ratio (Kenpeiritsu)', and the maximum ratio of total floor area of all stories to site area is the 'floor area ratio (Yousekiritsu)'.

Calculation examples: On a 200 m² lot with a 60% coverage ratio and 200% floor area ratio, the maximum building area is '120 m²' and maximum total floor area is '400 m²'; with a 300% floor area ratio on a 200 m² lot, the maximum total floor area is '600 m²'.

Height and placement restrictions such as 'shadow regulations (Hikage kisei)' and 'setback slope limits (Shasen seigen)' ensure good living environments with sunlight, daylighting, and ventilation for surrounding lots and homes.

When continuously installing scaffolds/hoardings or parking a mobile crane on a public road for work, both a 'Road Occupancy Permit (Douro sen'you kyoka)' from the road administrator and a 'Road Use Permit (Douro shiyou kyoka)' from the police chief are required.

Key points


  • Building area / site area is 'building coverage ratio (Kenpeiritsu)', and total floor area / site area is 'floor area ratio (Yousekiritsu)'.

  • A 200 m² site (60% coverage, 200% FAR) allows 120 m² building area and 400 m² total floor area; 300% FAR allows 600 m² total floor area.

  • Using public roads for scaffolds or cranes requires both a 'Road Occupancy Permit' (road administrator) and a 'Road Use Permit' (police chief).
WordMeaning
Building coverage ratio (Kenpeiritsu) & Floor area ratio (Yousekiritsu)
Road Occupancy Permit & Road Use Permit
River Area & River Conservation Area (River Act)

Construction Recycling Act, Waste Manifests, Asbestos Reporting, Noise & Wastewater

Under the Construction Recycling Act, building demolition projects with a total floor area of '80 m² or more' require sorted demolition and recycling of four Specified Construction Materials: 'concrete, materials composed of concrete and steel, wood, and asphalt-concrete'.

Pre-demolition asbestos survey results must also be reported to the Labor Standards Inspection Office and municipality when the demolished floor area totals '80 m² or more'. Under the Noise and Vibration Regulation Acts, 'Specified Construction Work' must be reported to the municipal mayor 'at least 7 days before work begins'.

The waste-generating contractor ('prime contractor') is responsible for industrial waste disposal and must verify final disposal using an Industrial Waste Management Ticket ('Manifest'). Excavated soil (Zando) must be kept separate from wood chips and waste plastics.

Strongly alkaline wash water from concrete chutes and mixers must be neutralized rather than poured into drains, and muddy excavation water must be treated within standards using sedimentation tanks or turbid water treatment units before discharge.

Key points


  • Demolition of '80 m² or more' floor area requires recycling the 4 Specified Construction Materials and reporting pre-survey asbestos results.

  • Notify the municipal mayor at least '7 days before starting' noisy/vibrating Specified Construction Work.

  • The prime contractor tracks industrial waste with a Manifest, neutralizes alkaline concrete wash water, and treats muddy water in sedimentation tanks.
WordMeaning
Four Specified Construction Materials (Tokutei kensetsu shizai)
Specified Construction Work under Noise/Vibration Acts
Industrial Waste Manifest (Retained for 5 years)

Site Rules and Related Laws

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