Apartment Defects and Landlord Obligations: What your rental contract may really regulate

Imagine this: It's winter, the heating breaks down, mold is spreading, or a window is drafty. The landlord doesn't respond or shifts the costs onto you. According to the 2026 Tenant Barometer and reports from the Tenants' Association, defects and delayed repairs are among the most common complaints from tenants.

Many contracts try to shift repair obligations or rent reductions onto the tenant. Good news: You can spot the most important traps just by reading the contract.

On welfarecalc.ch you can view all 30 risk points regarding defects and maintenance completely free – without uploading a contract. We explain the most common traps here as simply as if your 5-year-old self were listening.

Let's go!

1. “Tenant bears all repairs and maintenance costs”

📄 Original clause in the contract (common):
“The tenant assumes all maintenance and repair costs, including major repairs to the heating, electrical, and sanitary systems.”

⚠️ Why is it dangerous? According to Art. 256 and Art. 259 of the Swiss Code of Obligations (OR), the landlord is fundamentally responsible for maintenance and major repairs. The tenant only has to cover “minor maintenance” (simple tasks that can be done without specialized knowledge). Such blanket clauses are generally invalid.

🧒 Child-friendly explanation: If the heating breaks or the roof leaks, it's like a broken school bus – that's the driver's (landlord's) responsibility, not yours.

✅ What you should do: Only pay for minor repairs up to approx. CHF 150–200 per case (without a specialist) yourself. Major issues must be fixed by the landlord.

2. Waiver of rent reduction for defects

📄 Original clause:
“The tenant waives any reduction in rent, even in the case of significant defects or disturbances to the residential use.”

⚠️ Why is it dangerous? According to Art. 259d OR, you are entitled to a proportionate rent reduction (also retroactively) for defects that diminish the use value (e.g., drafty windows, lack of heating, mold). A pre-formulated waiver is void.

🧒 Child-friendly explanation: If there's a hole in the roof of your room and it rains in, you're allowed to pay less allowance until it's fixed. No one is allowed to simply take this right away from you.

✅ Correct approach: Always report defects in writing (by registered mail) and demand a reduction.

3. No deadline or delayed remediation by landlord

📄 Original clause:
“The landlord will remedy defects within a reasonable period, but the tenant is not allowed to set a deadline.”

⚠️ Why is it dangerous? You are allowed to set the landlord a reasonable deadline (e.g., 14 days). If they do nothing, you can carry out a substitute performance (repair it yourself and claim back the costs) or deposit the rent (Art. 259g OR).

🧒 Child-friendly explanation: If you say “please fix this by next week,” the landlord can't just reply “sometime.”

4. Excessive minor repair clause (e.g., 1% of annual rent)

📄 Original clause:
“The tenant bears all repairs up to 1% of the annual rent per year.”

⚠️ Why is it dangerous? Percentage clauses or excessively high amounts for “minor maintenance” are invalid. The decisive factor is whether the repair can be done without specialized knowledge and with simple means.

🧒 Child-friendly explanation: The landlord can't simply say “you pay for anything under 500 francs yourself” – it depends on whether you can fix it yourself.

5. No regulation regarding the defect list upon move-in

📄 Original clause:
“The tenant confirms that the apartment is free of defects at the time of handover.”

⚠️ Why is it dangerous? You should always create a handover protocol with photos and a defect list. Otherwise, existing defects could later be attributed to you.

🧒 Child-friendly explanation: Before you take the new toy, you look carefully to see if there are already scratches – otherwise nobody will believe later that you didn't make them.

6. Landlord not liable for certain defects (e.g., mold, noise)

📄 Original clause:
“The landlord is not liable for mold growth or external noise.”

⚠️ Why is it dangerous? The landlord is liable for structural defects (e.g., inadequate insulation) that impair the contractual use.

🔍 You now understand the most important defect traps

With this knowledge, you can report defects in a timely manner, enforce your rights, and avoid unnecessary costs. If you have your actual contract (in German, French, or Italian), you can have it checked on welfarecalc.ch free of charge and 100% locally in your browser – completely anonymous and secure.

Tip: Always report defects in writing (by registered mail) with photos and set a reasonable deadline. Use sample letters from the Tenants' Association.

📢 Share this article with friends who are looking for an apartment. Next post in the series: Notice periods and eviction protection in rental contracts – avoiding common mistakes.

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