不動産開発・建替え計画の進め方

Start with the Records, Not the Site

Japanese property redevelopment is an evidence problem before it is a construction problem. The most common error for newcomers is assuming that a single national database holds everything about a parcel. In practice, the documentation is fragmented: the Legal Affairs Bureau (法務局) keeps the land register and cadastral maps, the municipal planning department holds zoning and building confirmation files, and the tax office maintains the fixed-asset ledger. There is no unified private portal. A viable plan begins by identifying which local office holds each document for the specific parcel, then cross-referencing the entries.

This framework covers the research and planning steps for a Japanese property development or rebuilding project. It does not replace the advice of a licensed Japanese professional. Every figure, ratio, and legal rule below is tied to the named source and year; where a figure changes annually, the reader is directed to the current official publication.

1. Start with the Parcel, Not the Structure

Japanese property documentation is fragmented. A single project may require files from the Legal Affairs Bureau (法務局), the municipal planning department (市町村都市計画課), the tax office, and the family registry (戸籍). There is no unified private portal that combines all of them. The practical entry point is the parcel: its cadastral identifier, its registered owner, and its planning designation.

For an English-language researcher, the most useful first step is to obtain the following from the local Legal Affairs Bureau (法務局) that has jurisdiction over the property’s location:

登記簿 (land register), ownership, mortgages, easements, and other encumbrances
地図 (cadastral map), parcel boundaries, road access, and neighbouring parcels
登記識別情報 (registration identification information), the password-like code needed to file changes; without it, the owner must obtain a certificate of registered matters instead

The register is parcel-based, not owner-based. A single owner may hold multiple parcels, and one parcel may have multiple co-owners. The register is maintained by the Legal Affairs Bureau (法務局) that has jurisdiction over the parcel’s location, not a national central database. For practical research, identify the parcel by its land number (地番) and section (所在) on the cadastral map, then request the register for that specific parcel.

Why the Documentation Is Split Across Offices

The land register (登記簿) is held by the Local Legal Affairs Bureau (法務局) that has jurisdiction over the property’s location. The cadastral map (地図) is maintained by the same bureau but is not always fully integrated with the register, especially for parcels that have not been resurveyed under the cadastre mapping programme. Building confirmation applications (建築確認申請) are held by the municipal government that issued the permit, not by the bureau. Urban planning maps and zoning certificates come from the local government planning department (市町村都市計画課). The fixed-asset tax ledger (固定資産税台帳) sits with the municipal tax office. Inheritance documentation is in the family registry (戸籍) kept by the local municipality. Each document type lives in a different office, and the same parcel can appear with different reference numbers across these systems.

The Parcel Number Comes First

The first step is to obtain the parcel identifier from the official cadastral map (地図) at the Legal Affairs Bureau (法務局). The parcel number is the key that links the land register, the fixed-asset tax ledger, and the urban planning map. Without the parcel number, the remaining documents cannot be reliably located. The cadastral map is maintained by the Legal Affairs Bureau and is distinct from the land register itself. The land register records rights, ownership, mortgages, and easements, while the cadastral map records the physical boundary. Both are public and can be inspected at the bureau or ordered online through the Registration Information System (登記情報提供システム).

A property researcher should begin with the parcel number, then pull the register, then the cadastral map, then the planning map from the municipal planning department. The order matters because the land register identifies the parcel number, and the cadastral map confirms the physical boundary. A common mistake is to rely on a single source; the land register may show an owner, but the cadastral map may reveal a boundary dispute or an unregistered easement.

Step-by-Step Procedure

Identify the parcel. Obtain the parcel number from the current land register (登記簿) or fixed asset tax notice; if only an address is available, request a location map from the municipal tax office.
Pull the official land register. Visit the Legal Affairs Bureau (法務局) that has jurisdiction over the parcel, or use the online registration information system if available; request the 全部事項証明書 (all matters certificate) to see ownership, mortgages, easements, and any recorded restrictions.
Check the cadastral map. The 地図 is a separate document from the register; it shows the parcel boundary and may reveal access issues or overlaps.
Obtain a planning certificate (都市計画証明書) from the local government planning department to confirm zoning, FAR, and BCR for the parcel.
Review the building confirmation application (建築確認申請) for any existing structures; this shows the approved use, floor area, and structural type.
Search the koseki for inheritance chains if the owner is deceased; the land register alone may not show all heirs.
Check the fixed asset tax ledger for assessed value and structure details; this is a municipal document, not a market valuation.
Cross-reference the cadastral map with the land register to identify boundary discrepancies or unregistered easements.
Identify whether the parcel is in a Redevelopment Promotion Area or subject to urban redevelopment plans.
Engage a land and building surveyor for a boundary survey and a judicial scrivener for registration work; for larger projects, involve a real-estate appraiser and a lawyer.
Submit a building confirmation application to the local government; approval is a precondition for construction.
Document every finding in a written due-diligence report with source references and dates.

Key Variables to Compare Across Parcels

When assessing a Japanese property, a due-diligence process typically examines these practical variables:

Attribute	What to Check
Parcel area	Measured in square metres from the cadastral map
Floor-area ratio (FAR)	Maximum allowable floor area relative to parcel size
Building coverage ratio (BCR)	Maximum footprint percentage of the parcel
Zoning category	Determines permitted uses and density limits
Land price per square metre	From the published land price survey (地価公示)
Structure age	Affects seismic compliance and depreciation
Lease term remaining	For leasehold land, the years left on the ground lease
Number of co-owners	More co-owners increases negotiation complexity
Road frontage width	Narrow frontage may limit buildable area
Seismic rating	Newer structures built after the 1981 Building Standards Act revision are generally safer
Planning permission status	Whether prior approvals exist or have lapsed
Encumbrance count	Mortgages, easements, and other registered burdens
Relocation compensation band	If tenants must be relocated, the likely cost range
Site shape irregularity	Qualitative (regular, slightly irregular, severely irregular); regular is better for redevelopment, though irregular parcels may still be viable if the local authority allows a comprehensive redevelopment plan
Road access type	Public road, private road, or no road; public road access is best; a parcel with no road access may be landlocked and undevelopable
Historical designation	None, listed, or district; none is best for redevelopment freedom; a listed designation restricts demolition and alteration but may bring grants or tax incentives
Zoning change likelihood	Low, medium, high; high is better for redevelopment potential; actual zoning changes require public consultation and are rarely granted for a single parcel
Urban planning restriction	None, height, setback, or use; fewer restrictions are better; even a simple height limit can reduce the achievable FAR by 20-30%
Soil contamination risk	Low, medium, high; low is best; a past industrial use on the site is a red flag, and the official soil survey may not be public
Registration status	Registered, unregistered, or disputed; registered is best; an unregistered parcel may require a boundary survey and a new application to the Legal Affairs Bureau

Milestones for a Redevelopment Project

Verify the ownership and registration status of the target land in the official land register at the local Legal Affairs Bureau.
Confirm the zoning category, floor-area ratio, building coverage ratio, and any public facility reservations on the urban planning map.
Identify all encumbrances, including mortgages, easements, and leasehold interests, from the land register and lease documents.
Assess whether the current structure is subject to the Building Standards Act and whether any redevelopment would require a new building confirmation application.
Check whether the site lies in a Redevelopment Promotion Area or another special district that changes the applicable rules.
Determine whether the Land and Building Leases Act applies to existing tenancies and what notice periods or compensation obligations apply before demolition.
Establish a decision record: ownership shares, lease terms, registered encumbrances, planning certificates, and correspondence with co-owners or tenants.
Engage a licensed 土地家屋調査士 for boundary surveys and a 司法書士 for registration filings; involve a 不動産鑑定士 if a formal valuation is required.
Maintain a decisions log with dates, parties, and the source document for each fact so the record can be re-verified by a lawyer or bank.
File a Building Confirmation Application with the local government for new construction and retain the approval letter for the property file.

Boundaries and Limitations

This is a general educational overview and not a substitute for project-specific legal advice. Property laws, taxes, and planning rules change. The developer must verify all figures with the current official source and a licensed professional.