- 20 degrees by day, 18 degrees at night is what the heating must deliver during the heating season from October to April. Anything below that is a defect.
- The reduction starts when you report the defect to the landlord (§ 536c BGB), not when it occurs. Report it the same day, in writing.
- The percentage depends on the extent: a cold bedroom is not the same as a whole flat at 14 degrees.
- Reducing too much is risky: if two months' rent end up unpaid, you face termination. If in doubt, pay under reservation.
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How much can you reduce for a cold flat or heating failure?
During the heating season, usually October to April, the landlord must ensure 20 to 22 degrees in living rooms by day; at night, between 11 pm and 6 am, 18 degrees is enough. Even one or two degrees below that is a defect. The Higher Regional Court of Dresden granted a tenant 20 per cent for rooms that were too cold throughout the heating season.
If the heating fails completely, the percentage depends on the temperature that remains. At 14 to 15 degrees, courts have accepted up to 70 per cent. If the flat is practically uninhabitable in freezing weather, 100 per cent is possible.
A heating system that knocks or pumps is also a defect, typically in ground-floor flats above the boiler room: up to 15 per cent. The same applies if excessive heat from the boiler room rises into the flat above.
How much can you reduce without hot water?
Hot water is part of the flat, day and night. It must reach at least 40 degrees at the tap, and quickly. If it takes longer than about ten seconds or more than ten litres to run warm, courts have granted up to 10 per cent; the Regional Court of Berlin required 55 degrees after no more than three litres.
If the hot water fails completely, for instance because the central system is down, 15 per cent and more is usual. The Local Court of Darmstadt granted a tenant 30 per cent in winter. More on this under rent reduction for hot water failure.
How much can you reduce for leaky windows and draughts?
If draughts come through the windows, heat escapes and the rooms do not warm up. The landlord must seal the windows, in an old building as in a new one. Courts have granted up to 15 per cent for leaky windows. A reduction does not require the windows to be new: they must be as airtight as the condition of the flat promised when you moved in.
Measure and record the draught
One thermometer at the window and one in the middle of the room, readings noted with date and time, will convince the landlord, and if need be the court, more than any feeling.
How much can you reduce for mould?
Cool, damp air in winter is the ideal breeding ground. Whether you may reduce depends on the cause: if the mould comes from a structural defect, such as a thermal bridge or leaking walls, you reduce. If it comes from too little airing, you do not. Airing with the windows wide open for ten to fifteen minutes several times a day counts as sufficient.
The amount depends on the rooms affected and the health risk: for an infested living room, courts have granted 20 to 50 per cent, for mould in every room up to 100 per cent. What you have to prove and how an expert report helps is explained under rent reduction for mould.
How to proceed correctly
- 1. Report it immediately: Write to the landlord on the day of the defect, with date and description. From that day, the rent is reduced.
- 2. Set a deadline: Demand that the defect be fixed by a set date. For heating failure in winter, a few days is reasonable; otherwise about 14 days.
- 3. Document: Temperatures, photos, witnesses. One log entry per day is enough.
- 4. Reduce or pay under reservation: Cut the rent by the percentage, or pay in full “subject to reclaim” and recover the amount later.
- 5. Have it fixed yourself: If the deadline passes, you may hire a tradesperson and claim the costs from the landlord (§ 536a (2) BGB). Bring a witness.
How the percentage works out on your rent is shown in calculating a rent reduction.
The percentage applies to the gross rent
The reduction applies to the warm rent including service charges, not just the basic rent. At 20 per cent of 1,000 euros warm rent, you pay 800 euros.
Common questions about defects in winter
Can I reduce the rent without asking the landlord?
Yes, the reduction takes effect by law. But you must have reported the defect, otherwise you are entitled to nothing for the period before.
What if the landlord says the heating will not be repaired until next week?
The reduction still runs from your report. Whether the landlord is at fault is irrelevant for the reduction.
Do I have to pay for a fan heater myself?
The electricity costs of a fan heater you need because of the failure can be charged to the landlord as damages, if the landlord is responsible for the failure.
How long may the repair take?
For heating and hot water in winter: days, not weeks. Set a short deadline and announce that you will hire a tradesperson yourself after that.
Is your rent above the limit?
CONNY checks for free whether rent control applies to your flat and enforces the reduction. You pay only if we succeed.