This article explains the procedures for requesting repairs from your landlord when mold occurs in a rental property, considerations regarding cost allocation, and solutions if the problem cannot be resolved.
Reviewed by: Nobuyuki MoriPresident, M-Assets Co., Ltd. / Licensed Real Estate Transaction Specialist (Miyagi #018212)
When mold appears in a rental property, it's easy to think "I'll just clean it myself and be done," but if the mold stems from structural issues in the building (poor insulation, inadequate ventilation, water leaks, etc.), the landlord may have a legal obligation to perform repairs. This article explains the full process of requesting repairs from your landlord when mold damage occurs, how to think about cost allocation, and what to do if the issue escalates into a dispute.
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The allocation of costs when mold occurs depends on its cause.
Cases Where the Landlord Has a Repair Obligation:
In such cases, based on Civil Code Article 606, the lessor (landlord) has a duty to maintain the property in a condition suitable for use and enjoyment. Tenants can request repairs, and if the landlord fails to respond, they may demand rent reduction or claim damages (Civil Code Articles 611 and 559).
Cases Involving Tenant Negligence or Neglect:
In these cases, the tenant's use of the property is considered problematic, and they may be charged for restoration to original condition costs at move-out.
1. Document the Situation
When you discover mold, first take photos and videos with your smartphone. Documenting the extent, location (walls, floors, ceilings, window frames, etc.), and circumstances of the mold (such as signs of water leaks) will be important for later negotiations.
2. Contact the Management Company or Landlord Immediately
Contact the management company or landlord promptly after discovery. Delays in reporting may be interpreted as a breach of your duty of care as a tenant. Even if you call, follow up with an email or SMS documenting the details—this creates a record of evidence.
3. Don't Rush to Self-Repair
If there's a possibility the landlord has a repair obligation, prioritize having the management company assess the situation before you attempt thorough cleaning with mold removal products. Self-treating the problem first makes it harder to identify the cause and weakens your position in holding the landlord accountable.
Submit a Written Request
Telephone or verbal requests leave little documentation, so send a written request (email or registered mail) stating something like: "I discovered mold on [date]. As it appears to be a structural issue, I request repair work to address it."
Specific Repair Requests
Rent Reduction If Repairs Are Not Made
Civil Code Article 611 provides that if part of a rental property becomes unusable, the tenant can request a proportional rent reduction. If mold makes part of your living space unusable, you can exercise this right.
1. Consult a Consumer Affairs Center or Real Estate Consultation Desk
You can consult the Consumer Affairs Center in your prefecture or municipality, or the Ministry of Land, Infrastructure, Transport and Tourism's "Sumairu Dial" (Housing Reform and Dispute Resolution Support Center). Free legal advice is available.
2. File a Complaint Against the Property Management Company
If the management company is registered with the Ministry of Land, Infrastructure, Transport and Tourism as a rental property management company, filing a complaint against the company and providing information to authorities is also an effective option.
3. Small Claims Court
If damages are 600,000 yen or less, you can file a "small claims" lawsuit without an attorney. If you have sufficient evidence (photos, communication records, quotes, etc.), individuals can handle this themselves.
To prevent disputes over being charged for mold removal at move-out, record-keeping during your tenancy is crucial.
The guidelines state that "mold resulting from normal use is generally not the tenant's responsibility." However, if the cause is clearly inadequate ventilation or neglect of excessive humidity, that differs.
Don't give up on rental mold damage as unavoidable—it's important to identify the cause and handle it properly. If the cause is water leaks or structural ventilation problems, the landlord bears the repair obligation. Early documentation and written communication are your best tools for protecting your rights. If the problem persists, actively use consultation services like consumer affairs centers or Sumairu Dial.
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