Architects and Craftsmen in Japan: Running Your Renovation

The three roles to distinguish: architect, contractor, craftsmen

A successful renovation in Japan starts with knowing who is involved. Three roles coordinate, and mixing them up is the leading source of misunderstanding, especially remotely.

Party	Role	When they are essential
kenchikushi (kenchikushi, licensed architect)	Designs, draws plans, checks compliance, signs legal documents	Extension, structural change, permit application, seismic reinforcement
komuten (kōmuten, general contractor)	Prices, coordinates the site, employs or subcontracts craftsmen	Almost always: your main point of contact on site
shokunin (職人, trade craftsman)	Delivers one specific trade (carpentry, plaster, roofing, tatami)	Always, but via the komuten; rarely direct for a foreigner
sekkei jimusho (設計事務所, architecture firm)	Practice employing one or more kenchikushi	For an ambitious or bespoke design project

For a simple refit, a good komuten is often enough. As soon as you touch the structure or need a permit, the kenchikushi becomes mandatory. This is the starting point of all machiya and kominka renovation costing.

The kenchikushi: first- and second-class licensed architect

In Japan the architect title is regulated by the kenchikushi-hō (kenchikushi法, Architects Act), overseen by the Ministry of Land (MLIT). Two main tiers exist:

• ikkyū kenchikushi (一級kenchikushi, first-class architect): national licence, allowed to design any type of building, including large blocks.
• nikyū kenchikushi (二級kenchikushi, second-class architect): prefectural licence, sufficient for most single houses and small renovations.

For a house or an akiya to renovate, a nikyū kenchikushi generally covers the need. The kenchikushi is essential once the project needs a permit (see below) or a seismic reinforcement (shin-taishin): only they can sign the documents filed at city hall.

Finding and selecting your team

Finding the right komuten is harder remotely than finding a property. A few principles limit mistakes.

Where to look

• local komuten, rooted in the property's region: they know old buildings, the craftsmen and the municipal rules;
• sekkei jimusho firms specialised in heritage if you are renovating a machiya or kominka;
• referrals from the estate agent, the city hall or an on-site advisor.

How to select

• ask for references on comparable jobs (old buildings, same roof type);
• require a line-by-line quote (see next section), not a vague lump sum;
• judge responsiveness and clarity: a good partner explains, a bad one dodges.

Common mistake: underestimating the trust barrier

Many firms hesitate to work with an absent foreign owner, fearing misunderstandings and late payment. It is not ill will: to them it is a risk. A credible local relay (advisor, manager) removes that barrier. Our buying support acts precisely as a trusted third party between you and the site.

The mitsumori quote and the contract

The mitsumori (見積, quote) is the central document. A good mitsumori is detailed: it lists each item, quantity, unit price and subtotal. Avoid the single-line lump-sum quote.

What a good mitsumori must contain

• demolition and rubble removal;
• structure: roof, frame, foundations, reinforcement;
• second fix: plumbing, electrics, insulation, joinery;
• finishes: plaster, floors, tatami, paint;
• architect fees and permit costs;
• a contingency margin (old buildings always spring surprises).

Ask for two to three quotes against the same brief. Once the komuten is chosen, a works contract (kōji ukeoi keiyaku, 工事請負keiyaku) sets the price, schedule, payment stages and penalties. Never pay the full amount upfront. Always compare the estimate with your overall project budget, which you can test with our yield simulator.

The kenchiku kakunin building permit

Not every renovation needs a permit, but some do. The kenchiku kakunin (kenchiku kakunin, building compliance confirmation) is the clearance issued before works when the project requires it, under the oversight of MLIT and local authorities.

When a permit is required

• extension or floor-area increase;
• major change to the load-bearing structure;
• rebuilding (impossible on saikenchiku fuka, saikenchiku fuka, non-rebuildable land);
• significant change of building use.

When it usually is not

• interior renovation without touching the structure;
• redoing finishes, kitchen, bathroom.

Only a kenchikushi can file and sign the kenchiku kakunin application. On an old akiya, check this before buying: a project needing a permit on non-rebuildable land is a classic trap.

Running the site remotely: language, schedule, payments

Running a site from abroad is possible but demands method. Three topics make the difference.

Language

Almost all komuten and shokunin work only in Japanese. Without a bilingual go-between, every exchange risks error. A relay who translates and clarifies technical intent is essential.

Schedule

Set a written schedule with milestones: demolition, structure, second fix, finishes, handover. Build in a margin: old buildings spring surprises (frame, damp) that push stages back.

Staged payments

Payment is made in several stages tied to progress, never all upfront:

1. deposit at signing;
2. payment at start / structural works;
3. mid-point payment;
4. balance at handover, after inspection.

The handover (end-of-works inspection) must be done by you or a trusted proxy before the balance. Without a presence on site, an advisor who checks progress and validates each stage protects your money. This is the core of our buying support, shown in our tracked projects.

Common traps and the role of support: conclusion

Renovating in Japan remotely is entirely feasible, provided you avoid four recurring traps: 1) the one-line quote hiding items; 2) paying in full upfront; 3) the language barrier turning a misunderstanding into an overrun; 4) the firm reluctant to deal with an absent owner.

The defence rests on three reflexes: clearly distinguish kenchikushi, komuten and shokunin; require a detailed mitsumori and a staged contract; and rely on a trusted local relay who speaks the language, checks progress and validates payments. That is exactly the role of tailored buying support, from property search to site handover. To go further, cost your project with our detailed renovation costs and browse our supported projects.

Frequently asked questions

Do you need an architect to renovate a house in Japan?

Not always. For an interior renovation without touching the structure, a good komuten (general contractor) is enough. A kenchikushi (licensed architect) becomes mandatory once you need a kenchiku kakunin permit, a structural change, an extension or seismic reinforcement: only they can sign the documents filed at city hall.

What is the difference between a kenchikushi and a komuten?

The kenchikushi (kenchikushi, licensed architect) designs, draws plans, checks compliance and signs legal documents. The komuten (kōmuten, general contractor) executes the works: it prices, coordinates and employs or subcontracts the shokunin craftsmen. The komuten is your main site contact; the kenchikushi handles design and legal filings.

How do you read a mitsumori renovation quote in Japan?

A good mitsumori (見積, quote) is detailed line by line: demolition, structure, second fix, finishes, architect fees, permit costs and a contingency margin, each with quantity and unit price. Avoid the single-line lump sum, ask for two to three comparable quotes, and sign a kōji ukeoi keiyaku contract fixing price, schedule and payment stages.

Can you run a renovation remotely from abroad?

Yes, but with method. Almost all komuten and craftsmen work only in Japanese, so a bilingual relay is essential to avoid misunderstandings. Set a written schedule with milestones, pay in stages tied to progress (never all upfront) and have each stage plus the final handover validated by a trusted proxy on site.

When is a building permit required for a renovation?

The kenchiku kakunin (kenchiku kakunin) permit is required for an extension, a major change to the load-bearing structure, a rebuild or a significant change of use. It is generally not required for an interior renovation or redoing finishes without touching the structure. Only a kenchikushi can file and sign the application.