Incorrect Apartment Size Provides no Grounds for Increase in Rent

A proprietor wanted to retrospectively increase the rent up to the “local rent” (= “ortsübliche Miete”) because the apartment turned out to be larger than written in the contract. Since the tenant refused, the landlord filed a suit. After going through the lower courts, the BGH decided on this case on May 20, 2007 (re VIII ZR 138/06).


Plaintiff is a landlord and defendant is the tenant of a four-room apartment. The contract describes as “living space” (= “Wohnraum”) 121.49 m² instead of actual 131.80 m². The property owner wanted to raise the rent and demanded the acceptance from the tenant. When computing the new rent, the proprietor applied the general rules on raising the rent – based upon the actual size of the apartment and not the size stipulated in the contract. The defendant refused to accept.

The BGH decided in favor of the tenant. The court applied the “10% rule” in accordance with its ruling case law. According to this rule, the size of an apartment mentioned in a contract is not an non-binding description but a legally binding agreement. This rule was developed when tenants wanted to reduce the rent because their apartment was smaller than in the contract. In analogous application of this 10% rule, the landlord may increase the rent up to the local rent of the larger size only if the difference between agreed and actual size differs by at least 10%. Any difference below 10% will be considered as an irrelevant error and not as a defect of the apartment. In this case, the difference between the actual and the agreed space is, at 10.31 m², less than 10%. Therefore, the proprietor has no right to raise the rent just because he noticed that the actual size differs from the agreed size.

However, if the landlord in good faith had noticed that the contract shows less than the actual size, he would be entitled to raise the rent in accordance with the general rules in §558 I BGB to the local rent. This is an exception to the general rule that it is the landlord’s risk if he wrongly computes his remuneration for standing contracts like a rental contract. If it were not for renting a private apartment, the proprietor would be entitled to properly terminate the contract and offer the tenant to renew the contract according to the correct size. Whenever it comes to renting apartments for private reasons, the tenant enjoys a high degree of protection in Germany. This justifies the exception that the proprietor would otherwise have to wait until he has legal grounds for terminating the tenancy.

Published on the old CMS: 2007/7/30
Read on the old CMS till November 2008: 297 reads

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