Leasable area

The rental area refers to the area of a property that is made available to a tenant for use and on the basis of which the rent is calculated. Depending on the type of use and the agreed calculation method, the rental area may differ significantly from the actual living area or the gross floor area. For both tenants and landlords, a clear definition of the rental area in the lease is crucial because it directly influences the rent amount and potential claims for rent reduction.

Living Area According to the Living Area Ordinance (WoFlV)

In residential tenancy law, the living area as defined by the Living Area Ordinance (WoFlV) is the applicable standard. According to this, full-floor areas are counted in full, areas under sloped ceilings starting at a height of 1 m are counted proportionally, and balconies, terraces, and loggias are counted at one-quarter (in exceptional cases, at one-half). Basements, boiler rooms, and garages do not count toward living space. If the actual living space deviates by more than 10% from the area specified in the contract, the tenant generally has a right to a rent reduction.

Calculating living space according to the WoFlV sounds simple, but is complex in practice. Sloped ceilings are calculated using a graduated system: areas with a ceiling height of less than 1 m are not counted at all; areas between 1 and 2 m in height count for half; and areas with a ceiling height of 2 m or more are counted in full. For attic apartments in Nuremberg’s Wilhelminian-style buildings-often with irregular floor plans and varying ceiling heights-a correct calculation according to the WoFlV frequently results in a smaller area than previously stated in the lease agreement.

Commercial Leasable Area According to GIF Guidelines

For commercial real estate, the guidelines of the GIF (Society for Real Estate Research) generally apply, particularly the MF/G (leasable area for commercial space). This includes all usable interior spaces, including a proportionate share of common areas (hallways, restrooms, lobbies). The GIF area definition often results in larger reported areas than the WoFlV-an important point of comparison in commercial lease negotiations.

In the commercial sector, the agreed-upon area definition is legally binding under contract law-the law allows for considerable flexibility here. Tenants of commercial space who sign a contract based on the GIF area cannot subsequently invoke a smaller WoFlV calculation. The choice of calculation method should therefore be explicitly negotiated before the contract is concluded.

Leased Area and Area Discrepancies in Disputes

If a tenant determines that the actual area is smaller than specified in the contract, they may demand a pro-rata refund of the excess rent paid (retroactively up to three years after the standard statute of limitations). To determine the actual area, a measurement-if necessary by an expert-is required.

The 10-percent threshold serves as the materiality threshold: Only if the discrepancy exceeds 10% does a defect exist that entitles the tenant to a rent reduction and a refund. For a contractually specified area of 80 m², this would be the case if the actual area is less than 72 m². The tenant bears the burden of proof regarding the actual area-in disputed cases, a measurement by an independent expert is recommended.

Practical Tip for Landlords in Nuremberg and Franconia

In Nuremberg’s Wilhelminian-style buildings with sloped surfaces, niches, and irregular floor plans, the living area calculated according to the WoFlV often differs from the square footage specified in the old lease or purchase agreement. We recommend that owners have a correct measurement conducted in accordance with the WoFlV before re-letting-this avoids future disputes and ensures that the rent is based on a reliable area calculation.

This is particularly relevant when purchasing existing properties: If you buy an apartment and the purchase agreement states 75 m², but the actual WoFlV area is only 68 m², your rental income and purchase price are calculated to your disadvantage. A professional measurement before the purchase protects you from this pitfall. Upon request, we coordinate such measurements for prospective buyers before the notary appointment.

Frequently Asked Questions

As a landlord, am I allowed to state the rental area as larger than the living area according to the WoFlV?

No. Deliberately providing a false area measurement can be considered fraudulent misrepresentation. Even an unintentional deviation of more than 10% entitles the tenant to a rent reduction and a refund.

Does the 10% limit also apply to commercial leases?

For commercial properties, the legal situation is less clear-cut-the 10% limit stems from residential tenancy case law. For commercial leases, the contractual agreement and the specific definition of the area are more critical.

Does the basement count toward the rental area?

Under residential tenancy law, no-basements and storage rooms outside the apartment do not count under the WoFlV. However, if a basement is rented separately, it can be agreed upon as a separate rental area.

How much does a professional measurement cost, and who performs it?

A measurement by an architect or expert costs between 150 and 500 euros, depending on the size of the apartment. Real estate appraisers and building experts offer this service. The result is legally binding and can be used as evidence in disputes. In the Nuremberg metropolitan area, there are several experts who specialize in living space calculations.

Rentable Area and Indexed Rents: Significance for Rent Adjustments

In the case of index-linked lease agreements-now particularly common in commercial leases, but also in residential leases with index clauses-the rentable area specified in the contract forms the basis for calculating all future rent increases. If the initial floor area is incorrectly stated, this leads to a distortion of all subsequent rent adjustments. An area stated as too large results in all percentage increases being calculated on an inflated basis-to the detriment of the tenant and to the benefit of the landlord. Conversely, an area stated as too small leads to a permanent underestimation of the rental value.

We recommend that landlords in the Nuremberg metropolitan area always use a verified floor area calculation when drafting or revising index-linked lease agreements. Particularly in the case of existing apartments in Wilhelminian-style buildings, where the floor area has been carried forward for decades without verification, a review can reveal significant discrepancies.

Does the 10% tolerance limit from residential tenancy law also apply to commercial spaces?

No. In commercial tenancy law, there is no legally defined tolerance limit for area discrepancies. The Federal Court of Justice’s (BGH) case law regarding the 10% limit applies exclusively to residential tenancies. In the case of commercial leases, it depends entirely on the contractual agreement: If a specific area is agreed upon as being of the agreed quality and the actual area differs, a defect exists-but the materiality threshold and the legal consequences are determined by the individual contract and the general warranty rules under the law of obligations. Commercial tenants should therefore always verify the area specifications in the lease agreement by taking their own measurements before signing the contract.

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