Short answer: there is no official nationwide price list for renovating an akiya (空き家, an empty house), so any single "typical cost" would be a guess. The cost depends on the roof, the structure, the plumbing, the septic tank, termite damage and how much you want to change. The official pages this guide could open do not publish per-item prices. What they do give is a seismic-retrofit guideline from one prefecture, examples of municipal subsidies, and an official service that checks reform estimates. So the dependable method is a written, itemised quote from several local contractors for the exact house, ideally before you sign the sales contract. The sections below show how to read that quote and where to look for subsidies.
Japan's Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has a page on housing reform support systems (住宅リフォームの支援制度, dated 2 June 2025). It lists national programmes for earthquake resistance, energy efficiency and care-related modifications, and links to a search site for local government reform subsidies. It gives no price table. For seismic work it says many municipalities subsidise diagnosis and retrofit, that eligibility varies, and that you should contact the city or ward office.
The one cost figure this guide could confirm on an official page comes from Kochi Prefecture. Its housing earthquake-proofing page says that for a retrofit aiming to keep the house from collapsing in strong shaking, the construction cost guideline is ¥7,000 to ¥20,000 per square metre. The page does not state which years the figure is based on, and it is one prefecture's guideline, not a national average. As an illustration only, a 100 m² floor area would be ¥700,000 to ¥2,000,000 at that rate. A real quote can fall outside the range, particularly for an old, damaged or irregular building.
For everything else (kitchen, bath, toilet, roof, exterior walls, termite treatment, water supply and drainage pipes), no price from an official or industry-association page that opens in full could be confirmed. Industry survey documents found during research were PDFs that could not be read, so they are not quoted. Rather than repeat unsourced numbers from contractor marketing sites, the table shows what drives each cost and where to get a real figure.
| Item | What moves the price | How to get a number |
|---|---|---|
| Kitchen, bath, toilet (水回り) | Whether you keep the layout, the condition of the floor and walls beneath, and the pipe route | Itemised quote with fixture grades named |
| Roof and exterior walls (屋根・外壁) | Roof type, area, scaffolding, and whether the structure beneath is sound | Quotes with area and unit price per item |
| Termites (白蟻) | Active damage or prevention only, and how much timber must be replaced | Written inspection report, then a treatment quote |
| Seismic retrofit (耐震補強) | Floor area, year built, existing walls and foundation. See pre-1981 homes and the old seismic standard | Seismic diagnosis first, then a retrofit design and quote |
| Water supply and drainage pipes (給排水) | Pipe age and material, and the distance to the street connection | Plumber's on-site check |
| Septic tank and propane gas (浄化槽・プロパン) | Tank type and condition, and who owns the gas cylinders and piping | See the jokaso septic tank guide; ask the gas supplier directly |
If the lot cannot legally be rebuilt on, or sits in a zone where building is restricted, the plan "renovate now, rebuild later" may not be available, and large structural changes can be harder to justify. Read our guide to rebuilding-prohibited lots and urbanization control areas before you fix a renovation budget. If demolition is the better route, compare it with the demolition cost and subsidy guide.
An empty house is a target for door-to-door roof and exterior sales. The National Consumer Affairs Center of Japan reported on 11 October 2023 that complaints about roof-work inspection sales reached 2,885 in fiscal 2022, the highest in five years, and that over 80% of the contracting parties were aged 60 or older. Its advice: do not let an unexpected visitor inspect your roof, do not sign a roof contract on the spot, and be cautious of claims that insurance will pay. The national consumer hotline is 188.
The official existing-house inspection covers structure and rain intrusion only, so plumbing, termites and the septic tank can still be unknown. Our home inspection guide explains the scope. Anything the inspection does not cover needs its own quote.
The same service, run by the Housing Reform and Dispute Settlement Support Center (住宅リフォーム・紛争処理支援センター), offers free consultation on a reform plan or a contractor's estimate through the 住まいるダイヤル line (0570-016-100). It is a Japanese-language service, so a Japanese-speaking helper may be needed.
Refonet suggests shortlisting roughly three to five contractors and asking each for an estimate. Give each the same written brief and the same photos or drawings, so the differences you see are in price and method, not in the job. Prefer contractors who will visit the house; a quote without a visit is the situation MLIT warns about. Do not choose on the lowest total alone: check that each quote covers the same items, including waste removal and the finishing work around any structural repair.
Subsidies for akiya renovation are mostly set by each municipality. As one example, Bizen City in Okayama runs an akiya renovation promotion subsidy that covers up to one half of eligible costs, capped at ¥500,000. The work must total at least ¥300,000 including tax and be done by a local builder. The house must be on the city's akiya information bank, be rented out for at least one year after renovation, and the applicant must consult the city in advance. Note that this scheme is aimed at owners renovating to rent, so a buyer who plans to live there may not qualify. This is one city's rule, not a national standard.
At the national level, MLIT's page above points to the housing safety stock programme for seismic work, delivered through municipalities, and to a search site for local reform subsidies. To check your own case: find the municipality of the house, search its site for 空き家 改修 補助, 耐震改修 補助 and 空き家バンク, then ask the office whether you must apply or consult before the sales contract or before work starts, and whether the scheme is open to a non-resident or foreign buyer. Our guide to the Wakayama akiya bank shows what that process can look like for one prefecture.
The earlier the better, but within limits. After you have a shortlisted house and before you sign the sales contract, ask the agent whether a contractor may view the property. A contractor's rough written quote lets you check the asking price against the likely repair cost. Read the contract's cancellation terms first (see deposit and cancellation), and treat a pre-purchase quote as provisional. Also budget acquisition and ownership costs, covered in this guide to taxes and fees.
There is no official nationwide price list, so any single figure would be a guess. Cost depends on the roof, structure, plumbing, septic tank and termite damage. The one official guideline cited here is Kochi Prefecture's ¥7,000 to ¥20,000 per square metre for a seismic retrofit. For everything else, get written, itemised quotes for the specific house.
Subsidies are run by each municipality and the rules differ. Many are tied to the akiya bank, to using local contractors, to living in or renting out the house for a set period, and to consulting or applying before work starts. Whether nationality matters is a question for the municipality office, so ask them directly for the current rules.
Where the seller and agent allow a site visit, a rough written quote before signing the sales contract lets you price the house realistically. Check the contract's cancellation terms first, and treat any pre-purchase quote as provisional until the contractor has seen everything.
Have a specific listing in mind? Get the official zoning, hazard and transaction data for that exact lot — plus the questions to send the agent — in one report.
Get a $49 risk report Free 12-point checklistThis guide is general information based on public sources cited above. It is not legal, tax, or real-estate brokerage advice. Confirm every item for a specific property with the agent, the municipality, and licensed professionals.