Rent Reduction for Mold: A Guide to Your Rights

Danger to Health and Wallet

Mold in the apartment is far more than just a cosmetic problem. It poses a significant health risk and is legally a clear defect of the rental property. This means: You don't have to tolerate this condition and have the right to reduce rent. However, you must proceed correctly to avoid making yourself vulnerable.

This guide shows you the necessary steps.

The Legal Basis: Your Right to a Defect-Free Apartment (§ 536 BGB)

The German Civil Code (BGB) is on your side here. The landlord is legally obligated to provide you with the apartment in a habitable, defect-free condition and maintain this throughout the entire rental period. If a defect like mold occurs, this obligation is violated, and your right to rent reduction arises.

Step 1: Defect Notification – Do It Right!

This is the absolutely most important step that determines success or failure. Before you reduce rent, you must notify the landlord of the defect.

• Written form: Always do this in writing, preferably by registered mail, to have proof.
• Deadline setting: Give the landlord a reasonable deadline to eliminate the mold (e.g., 14 days).
• Documentation: Take detailed photos of the infestation.

Warning: If you simply reduce rent without correctly and demonstrably reporting the defect, you fall into payment default and risk termination.

How High Can the Reduction Be? (With Examples)

The amount of reduction depends on the severity of the infestation. There are no fixed tables, but court decisions provide good guidance:

• 5-20% reduction: For light to moderate infestation in a corner or on a wall.
• 50% reduction: For severe infestation in important rooms like living or bedrooms.
• up to 100% reduction: When the entire apartment becomes uninhabitable due to mold.

Be realistic in your assessment. An overly high reduction can also lead to termination risk.

Special Case: Immediate Termination in Case of Health Hazard

If the mold poses a significant health hazard and the landlord remains inactive after your defect notification, you may even have the right to immediate termination for important cause (§ 543 BGB).

Secure Your Position Contractually

Before you make a reduction or even declare termination, you must be absolutely certain that your rental contract contains no pitfalls. Some contracts contain invalid clauses about defect notification or minor repairs that the landlord could use against you.

A mistake in the procedure can become expensive.