How to calculate the living space correctly

How to calculate the living space correctlyReal estate is sold by square meter. Here, however, interested parties should secure themselves by precise measurement, because in many cases the stated square meter numbers are not correct. Above all, the respective calculation method plays a role and so different information comes about for the same living space.

Calculation using a certain method?

There is no fixed method for calculating the number of square meters in Germany – so real estate sellers can use different types when it comes to determining the respective living space. Stiftung Warentest even assumes that in two out of three cases the living space is not calculated correctly and that more than one square meter deviate from the real number. Those interested in real estate should therefore study the underlying method in detail and only compare sales offers on the basis of the same calculations.

On the one hand there is the possibility of calculation according to the DIN standard, on the other hand the living space regulation can be applied. The DIN standard even has to be subdivided again and is differentiated into DIN 277 and DIN 283. However, the latter standard is out of date and is rarely used. If no other method of calculation is agreed in the purchase or rental contract, the calculation according to the DIN standard applies.

What is part of the living space?

The basement of an apartment or house, the laundry room or even the boiler rooms and garages are not included in the living space. Conversely, however, the areas on which, for example, ovens and bathtubs are located, on which built-in furniture is placed or which are used by doors and windows, also count as living space. It is important when calculating the living space how high the room is.


  • Areas under a slope are part of the living space if they are more than one meter high. Up to a room height of two meters, however, they are only credited to 50 percent. The area under a slope up to a room height does not count towards the living space.
  • All rooms and parts of rooms that have a room height of at least two meters are credited 100 percent.
  • The same principle applies to areas under a staircase, here too the 100 percent living space only begins with a room height of two meters.
  • Pillars, columns, facing walls and chimneys are not part of the living space, provided they occupy an area of 0.1 square meters and are higher than one meter.
  • The niches of windows, doors and walls do not count towards the living space. If the niches reach the floor, they must be at least 13 centimeters deep in order to be eligible.
  • If conservatories and swimming pools are not heated, they only count to 50 percent of the living space.
  • Balconies, terraces and roof gardens should only count towards half, which is the maximum value. Usually they are added to a quarter.

Calculation according to the DIN standard

If the living space is calculated with the DIN standard 277, this has advantages for landlords and sellers, because this calculation is a little more generous. The starting point is the actual base area of the object. The first step is to determine the gross floor area, which results from the external dimensions of the property. Then the construction surface has to be subtracted, i.e. walls, pillars and all supports that are housed in the building. That gives the net footprint. This is now divided into three types of space, so that the functional, traffic and usable space result. Inhabited rooms are part of the usable area, storage rooms are functional rooms and corridors are part of the traffic areas. Usable and traffic areas are merged, resulting in the square meter of the property. All sloping ceilings, balconies and cellars are fully credited. The total area that can be rented or sold is therefore significantly larger. The differences to the first-mentioned calculation method can be serious and can be up to 40 percent. If an apartment or house is then calculated according to the Living Space Ordinance, a tenant or buyer can legally contest a rent reduction or a discount on the purchase price.

What if the living space is too small?

Tenants have the right to reduce the rent if the actual living space deviates by ten percent or more from the space agreed in the rental agreement. However, this principle can only be applied to sales contracts to a limited extent; here courts generally have to decide on a reduction. In 2003 court rulings, the Federal Court of Justice determined that every percentage point by which a landlord miscalculated may be deducted from the rent. The advance payments on the additional costs may then be reduced to the same extent. For the future, the landlord must then set the actual living space in the service charge settlement. By the way, a tenant can even get part of his deposit back, because the maximum amount of the deposit may be three months’ rent.

Rights of tenants and landlords

If the specified living space exceeds the real one by more than ten percent, the rent reduction just mentioned applies. If this is not the case and the living space deviates by less than ten percent, the tenant cannot demand a discount. Important: If the landlord has guaranteed the living space, it must also be correct. If a rental price has been agreed that is based on the square meters, the courts see this as an assurance for the specified square meters. Landlords therefore often try to keep a loophole or two open. An example: In the lease agreement there is a non-binding indication of the living space. Measurement errors are not excluded, the living space is not part of the rental object. If approximate information can be found in the rental agreement, these are however binding.

It is also possible that no information about the living space can be found in the rental agreement, then it is important what was in the real estate ad or what the floor plan says. However, the square meters must be named when it comes to calculating the additional costs. Here tenants can still take their chance and measure the living space. This can result in a reduction in payments.

However, the living area regulation only applies if nothing else has been agreed. If the landlord or seller refers to DIN standard 277 in the contract, the area can be larger than measured. However, special rules apply to sales contracts: The square meters stated should not be binding for buyers – deviations and resulting claims usually have to be disputed in court.

A tenant can, if he has recognized the landlord’s error, reclaim the overpaid money by letter of formal notice, complaint or (if there is goodwill) a letter. The recovery may relate to the last three years, whereby the calendar year is fundamental. The landlord can exercise his right of limitation here, even if the “overpaid” period is significantly longer than three calendar years ago.

Good advice at the end

  • Tenants or buyers should definitely measure whether the specified living space in the contract is correct. If nothing has been agreed here for the calculation of the living space, the Living Space Ordinance applies.
  • Buyers should measure the property before signing the purchase contract, because a reduction of the purchase price is very difficult afterwards. Many courts also refuse to claim damages.
  • Tenants should definitely first speak to the landlord and only then exercise their right to a reduction. An amicable settlement is preferable in any case!
  • If you are not sure about the measurement, you should consult a civil engineer or architect. They can also prepare a written report.


Photo credits: © – Mariamichelle

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