Mould in your home: whose responsibility is it?

Sep 25, 2023.

Whether it’s behind the bed, on the bathroom ceiling or in the cellar: mould is not only disgusting, it can also damage your health. If you live in a rented property, you depend on the landlord to take action. But who bears the cost of removal, and what can you do if the situation does not change? Answers to the most common questions about mould.

A German survey shows that every fifth home is affected by mould. It often grows undetected behind furniture, and sometimes quite obviously between the tiles in the bathroom. In most cases, the occupants cannot do much about it, because it is difficult for moisture to escape the room. However, difficult discussions with the landlord are unavoidable when it comes to professional removal of mould and the resulting costs.



What should you do if there is mould in your rented property?


As a tenant, you do not have to tolerate mould and should react as quickly as possible. It is a problem that the landlord must tackle. You are entitled to a rent reduction if the mould has developed through no fault of your own, as it is harmful to your quality of life. If the landlord does not act, you can exert pressure by withholding part of the rent. Do note the following, however: the landlord should not simply have the mould removed, but also eliminate its causes.


Here is the best course of action if you spot mould in your rented property:

  • Do not start cleaning the mould: the appropriate agents are aggressive and should only be used by professionals. You can carefully remove smaller traces of mould with methylated spirits (ventilate well!).
  • Report any mould you find in your home to the landlord as soon as possible – preferably by recorded delivery. If you wait too long, you could be held liable for consequential damages.
  • Take photos to document the defect. Measure the humidity and temperature in your home – this is also important evidence.



Who is to blame if mould develops?


In principle, the person who caused the mould is responsible. They must also cover the costs of removal. But with mould, the cause is often difficult to determine – the same applies to the question of liability.


Tenancy law states that landlords must be able to prove beyond doubt that the tenants are to blame for the mould infestation. This rarely succeeds. If you regularly ventilate, heat your home sufficiently and keep it clean, you cannot be blamed. Structural defects are the most common cause of mould, for instance if the interior insulation or the roof are leaking and too much moisture can penetrate.



What mould can do to your health


White and black mould can irritate the eyes, skin and respiratory system. Allergy sufferers and children are particularly vulnerable. Living in a mould-infested home can lead to pneumonia, chronic coughing and asthma. Mould often develops unnoticed on damp walls behind furniture – check these areas regularly.



How to avoid mould in your home


The best advice is as simple as it is obvious: ventilate your living areas several times a day for at least 10 minutes to allow moisture to escape. And heat your home properly. Humidity levels of less than 60% and a room temperature of 20°C are considered ideal.


In the bedroom: We lose up to 1.5 litres of water through sweating at night – usually without noticing. The bedroom therefore has a humid climate. That is why you should ventilate well in the morning to prevent moisture from condensing. If this is not possible, a special dehumidifier can help.


In the bathroom: This is where mould occurs most often because bathing and showering increases humidity. It is most likely to occur in the grout or on the ceiling. A built-in ventilation unit is essential if you do not have a window in your bathroom.


In the cellar: Cellars are often cold, damp places, which is particularly conducive to mould growth. It can develop quickly, especially on damp exterior walls. Cellars are often poorly sealed and ventilated, so a dehumidifier only helps to a limited extent. Talk to your landlord.


Fortuna Legal Protection Insurance – a subsidiary of Generali Switzerland – has been helping customers to access justice for 50 years. During this time, it has grown significantly and now applies the expertise and experience of over 100 employees in 31 branches of law.