Mold in your rented room: who has to fix it?

Black patches in the corner of your room, a musty smell that never goes away, or spots on your mattress and clothes: mold in a rented room is unpleasant and sometimes unhealthy. The tricky part is that landlords often say it is your fault, while the cause just as often sits in the building itself. This article explains how to spot the cause, who has to pay under Dutch law, and what to do if your landlord ignores it.

Where does mold in a rented room come from?

Mold grows where there is moisture. The real question is: where does that moisture come from? Roughly speaking there are three sources, and they decide who is responsible.

Structural moisture comes from the building: a leaking roof, rising damp in a ground-floor wall, poor insulation that makes cold walls sweat, or a broken mechanical ventilation system. This is almost always the landlord's responsibility.

Use-related moisture comes from daily life: showering, cooking, drying laundry indoors, breathing. A person releases more than half a litre of moisture into the air per night. If that moisture cannot escape because the room is never aired, it settles on the coldest spot and mold grows there.

A combination is the most common case: a poorly insulated room (building) that also gets little fresh air (use). Then responsibility sits with both sides, and it comes down to which cause is the bigger one.

When is the landlord responsible for the mold?

Dutch law treats mold from a building defect as a defect in the rented property that the landlord must fix. A landlord cannot contract this duty away: a clause saying all damp problems are the tenant's is void.

The landlord is responsible for:

• Leaks from the roof, pipes or window frames
• Rising or penetrating damp in walls and floors
• Poor or missing insulation that structurally makes walls sweat
• A broken or too-weak mechanical ventilation or extraction system
• Windows or frames that no longer close properly

Important: even if your ventilation habits are not perfect, the landlord stays responsible once it turns out the property is structurally unfit for normal living. A room should be possible to keep mold-free under normal use. If that only works with the windows open all winter, there is a defect.

When is it your responsibility as a tenant?

Sometimes it really is the use, and then the tenant is up. That happens when the room can be ventilated fine, but you structurally do not do it.

Down to you is mold from:

• Never airing or taping shut the ventilation grilles
• Drying laundry indoors without ventilating
• Pushing furniture tight against cold exterior walls with no room for air to circulate
• Not drying the bathroom after showering or switching off the extraction

What step-by-step plan gets the mold fixed?

1. Make it visible and measurable. Dated photos, and if possible a simple hygrometer showing the humidity. Above 60 percent for long periods is a sign of a moisture problem.
2. Report it in writing to the landlord. By email or letter, with a clear description and the photos. Ask for repair within a reasonable term (two to four weeks for non-urgent cases).
3. Send a reminder if nothing happens. Preferably by registered post, so you can prove you formally put the landlord on notice.
4. Bring in the Huurcommissie. With a regulated rent you can start a procedure over maintenance defects. The Rent Tribunal can impose a temporary rent reduction until the defect is fixed, a strong lever.
5. Report danger to the municipality. For serious mold or a health risk, Building and Housing Supervision can take enforcement action against the landlord.

How the Rent Tribunal works and what such a rent reduction yields is covered in our article on the Rent Tribunal procedure to lower your rent. Want to know which maintenance is the landlord's anyway, read about repairs in your rental and who pays.

How do you stop mold coming back?

Even after the landlord fixes the problem, it helps to keep your own part in order. Air the room thoroughly for fifteen minutes a day, keep furniture a few centimetres off exterior walls, dry laundry outside or in a ventilated space, and keep the ventilation grilles open. That also removes the "your own fault" argument if you ever need to report a defect again.

Renting a room with a live-in landlord (hospita)? The same rules about structural defects apply, so check our hospita regulation explainer for your position. Looking for a room where you can get ahead of surprises like this? On Huismaatje you see who you would live with and can ask the right questions about insulation and ventilation up front. For the full picture of your rights as a tenant in the city, see our pillar guide on renting a room in Amsterdam and the neighbourhood hub.

Frequently asked questions

Can I withhold rent while there is mold?

Not just like that. Stopping payment yourself is risky and can create rent arrears. The correct route is to request a rent reduction through the Huurcommissie, not to withhold rent on your own. When in doubt, get legal advice from the Juridisch Loket or the Woonbond.

The landlord says it is my own ventilation, is that true?

Sometimes yes, sometimes no. If the room should be possible to keep mold-free under normal use but demonstrably cannot be, there is a structural defect and the landlord is up. The burden of proving the cause does not automatically fall on you.

Does a hygrometer really help as evidence?

It helps to show a pattern. A hygrometer that records high humidity for months despite normal airing supports the case that the problem sits in the building. Always combine it with photos and your written reports.

Can I terminate my rental contract over mold?

For serious, unresolved defects you can, as a last resort, ask the court to dissolve the lease. That is a heavy route. Usually a rent reduction via the Huurcommissie is faster and more effective. See also how to properly terminate your rental contract if you do want to leave.

Who pays for my damaged belongings if the mold came from the building?

If the mold results from a defect the landlord knew or should have known about and did not fix, the landlord can be liable for damage to your belongings. Keep receipts and photos, and check if your contents insurance covers mold damage.