Mould in your apartment. Points to bear in mind.

If you find mould in your apartment, you’ll have lots of questions. Why has it happened? What should you do? Who is liable? And can you prevent mould growth?

How does mould form in your apartment?

Mould grows anywhere that damp is present. It could be caused by damaged water pipes, leaky windows or insufficient insulation of external walls, but a high level of humidity in the apartment also encourages mould growth. This can develop quickly as a result of everyday activities that release high levels of moisture into the air, such as showering, cooking or drying clothes. Add to this incorrect or insufficient ventilation, and you have the ideal conditions for mould to form.

Good to know

If you notice mould growth, you as a tenant are obliged to inform the landlord immediately. That way you can not only avoid possible damage to your health, but also prevent the spread of mould to other areas and objects. Photos documenting the extent of the mould can be very useful in cases like this.

Who is liable when mould is discovered in an apartment?

Mould in a rental property not only poses a health hazard for the residents – the cost of eradicating it can spoil your enjoyment of living there. Merely obtaining an expert opinion on the contamination can cost thousands of francs. As far as paying for the eradication of mould is concerned, the polluter-pays principle applies: whoever caused the damage ultimately has to foot the bill for it.

But, in practice, it is often impossible to establish who is responsible for mould in an apartment with any certainty. Determining who is at fault is often not possible without commissioning costly expert opinions. That’s why many such cases lead to disputes between tenants and their landlords that quite often end up in court, so that the legal position can be clarified.

Mould due to building defects

If the mould is attributable to a building defect, the landlord is liable for the damage. As the tenant, you are entitled to apply for a rental reduction for the period during which you are unable to use your apartment in line with the conditions of your rental agreement. The amount of the reduction corresponds to the extent to which you are unable to use your apartment.

Mould due to incorrect ventilation

If it can be clearly proven that you, the tenant, caused the mould by failing to ventilate the apartment properly, you are responsible for repairing the damage.

Which insurance policy pays out when mould is discovered in an apartment?

If your landlord is responsible for the mould, they are liable for the damage. Apart from the trouble and inconvenience involved, you will incur no additional costs.

However, if it can be definitively proven that you caused the damage, you must have the mould removed at your own expense. In such cases, the costs are not covered by household contents and private liability insurance.

Legal protection. Insurance cover in the event of legal disputes.

The question of who is responsible for mould in an apartment can quickly lead to legal disputes between tenants and their landlords. If the landlord blames you for the mould, even though you may not be responsible, it is advisable to contact the Coop Rechtsschutz legal protection team. They will advise you on next steps and support you with legal issues. In the event of a court case, legal protection insurance will cover lawyers’ fees and court and procedural costs for claims covered by the policy.

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How can you prevent mould growth in your apartment?

There are a few rules of thumb to avoid mould forming in your apartment:

Tip #1

Ventilate properly

Sufficient ventilation is the key to preventing mould, which is why experts advise you to air your apartment every day:

Five to ten minutes of flow-through ventilation, two to three times daily.
Fully open windows when airing. Windows should not be left constantly ajar, as this results in considerable heat loss.
The colder it is outside, the shorter the time needed for airing.
Don’t forget to air rooms located in the cellar.

Tip #2

Heat properly

The apartment temperature also plays an important role in mould formation. Cold air cannot hold as much moisture, which results in more condensation. This is a particular concern in poorly insulated buildings. If you prefer to turn down the heating in certain rooms, such as the bedroom, take special care that humidity can escape through correct ventilation, and close doors so that warm, humid air from other rooms cannot enter. In general, the indoor temperature should not fall below around 18°C.

Tip #3

Keep a check on humidity

Steam in the bathroom and kitchen produces a particularly high amount of moisture. Where there is a lot of steam, open the windows straight away or use the extractor fan to ensure it cannot settle on the walls. Do not dry your clothes in the apartment.

Your questions. Our answers.

Can I terminate my contract without notice if there is mould in my apartment?

In serious cases, where the extent of the mould means it is not feasible to live in an apartment, or to do so would cause damage to health, the tenant has the right to terminate their contract without notice. However, it is often unclear whether the mould growth can be regarded as sufficiently serious. If the arbitration office or court decides in retrospect that the defect is not sufficiently serious, the tenant must subsequently pay the rent. We therefore strongly recommend consulting the Coop Rechtsschutz legal protection team or the local tenants’ association and having the mould assessed before terminating the contract without notice.

Who has to remove mould from my apartment when I move out: me or my landlord?

If the landlord is responsible for the mould growth, they are obliged to remove the mould and cover the costs. They are also required by law to grant the tenant a rent reduction because their living conditions have been negatively impacted by the mould. However, if the tenant bears responsibility for the mould, they must have it removed at their own cost, at the latest by the time they move out of the apartment.