Commercial Maintenance in Lower Saxony: NNN Leases & Obligations

While in residential tenancy law maintenance costs are legally assigned almost entirely to the landlord, commercial landlords in Lower Saxony have extensive leeway. The passing on of considerable maintenance and repair risks to the lessee or tenant is the absolute standard in logistics, office, and retail portfolios.

Disclaimer: This guide provides an overview of commercial maintenance clauses and does not constitute legal advice. The formulation of such clauses entails extremely high legal risks ("AGB control"). Always consult commercial legal experts. Information last verified: March 2026.

1. The Legal Model (§ 535 BGB)

The German Civil Code initially stipulates for commercial properties as well that the landlord must maintain the rented property in a "condition suitable for contractual use." If a commercial air conditioning unit on the roof of an office building breaks down, theoretically the landlord would have to repair it at his own expense.

2. Shifting to the Tenant: Double Net (NN) and Triple Net (NNN)

In order to offer landlords of commercial properties (funds, insurance companies, project developers) a purely passive, secure "interest investment" without constant repair costs ("Drip-Feed Costs"), the maintenance obligations are contractually shifted massively to the tenant. This mostly happens via so-called "Net Lease" forms:

• Double Net (NN) Lease: In addition to the base rent, the tenant bears all ancillary costs, insurance (property tax), as well as all maintenance inside the building and the servicing of technical building equipment (ventilation, heating, roller doors, etc.). The landlord retains "roof and structure" (the constructive building substance such as the foundation, support structures, outer building envelope).
• Triple Net (NNN) Lease: The maximum solution. De facto, the tenant bears the complete risk for the maintenance of the building and the property (often in "Sale-and-Lease-Back" or when entire industrial halls are played by the tenant as the sole user).

3. General Terms and Conditions Law (AGB): The Limit of Shifting

A huge danger for landlords lurks here in Lower Saxony. If the shifting of costs is not negotiated individually and explicitly ("Individualvereinbarung"), any court evaluates the lease agreement as standardized "General Terms and Conditions" (AGB). And AGBs are subject to strict testing (§ 307 BGB).

What is Invalid in Standardized Forms / AGB:

• The form clause according to which the commercial tenant is assigned "roof and structure" (external wall, foundation) without exception is legally invalid in standard contracts! If a load-bearing reinforced concrete column breaks due to aging, the landlord will have to pay for it themselves despite this "NNN clause" (and may also have to pay damages to the tenant).
• Clauses that transfer the obligation to repair communal areas (e.g., roof air conditioning of a shopping center that also cools other shops) flatly without an absolute cap and the "polluter-pays principle" to the tenant are regularly invalid.
• Vague formulation on "maintain and care": The difference between routine maintenance (filter replacement) and genuine "repairs" or renewals (capital replacement costs) must be precisely separated.

4. Rent Reduction in Commercial

If a pipe damage in a logistical hall in Hanover minimizes operations, two mechanisms come into play:

1. Complete Exclusion of the Reduction: Format contractually (in the AGB) it is almost always agreed that any rights of reduction and rent abatement of the tenant in the event of defects are initially excluded. The tenant must continue to pay the full rent unreduced and may only reclaim reduced amounts ex post via his own court proceedings as a condition claim or unjust enrichment ("Solve et repete").
2. Duty to Remedy Defects: Even if the tenant is forbidden from reducing payments in the short term, the landlord is immediately forced to repair in the event of defects in his area of responsibility (usually building substance), otherwise astronomical claims for damages arise (business and loss of profit of the tenant).

optimally Coordinate Maintenance and Service Providers with Landager

In commercial real estate, the effort for maintaining highly complex technical systems (fire dampers, air conditioning units, roller doors, elevators) adds up enormously. Landager offers commercial landlords and their facility managers in Lower Saxony a structured ticketing system that monitors maintenance frequencies and seamlessly documents maintenance orders in a legally compliant manner.

Back to the Lower Saxony Commercial Tenancy Law Overview.