Germany: Rental rules for air conditioning installation

In Germany, tenants face specific legal restrictions regarding the installation of air conditioning units during extreme heat. Permanent split-system units are considered structural changes and require explicit consent from the landlord. In apartment buildings, approval from the homeowners' association (WEG) is also necessary, though a majority vote is typically sufficient.

Portable monoblock units generally do not require landlord permission as they do not involve drilling into walls. However, tenants must still seek permission for any structural modifications, such as passing exhaust hoses through windows. These portable units are noted to be less efficient and noisier than permanent systems.

While there is no legally defined maximum indoor temperature, temperatures consistently exceeding 28 to 30 degrees Celsius due to structural defects may allow tenants to seek rent reductions through court rulings. Tenants are advised to maintain detailed temperature logs to document such conditions.