Illegal construction

Illegal Construction - Illegal construction refers to a structure that has been built or significantly altered without the required building permit. The building authority may issue a prohibition on use or even an order to demolish the structure, which is why illegal construction carries significant legal and financial risks.

Legal Classification and Consequences

An illegal structure exists when a construction project requiring a permit is carried out without the appropriate building permit. This applies not only to entire buildings but also to additions, extensions, attic conversions, garages, carports, or the conversion of spaces-such as when a basement is converted into living space without a permit. The decisive factor is whether the project in question requires a permit under the Bavarian Building Code (BayBO).

If the building authority identifies an unauthorized structure, it has several tools at its disposal. First, it can issue a stop-work order prohibiting further construction work. Additionally, a prohibition on use is possible, which forbids the owner from using the building or the affected part of the building. The most severe measure is the demolition or removal order, under which the structure must be demolished at the owner’s expense. Additionally, fines of up to 500,000 euros may be imposed under administrative offense law.

A common misconception concerns the statute of limitations: In Bavaria, there is no true statute of limitations for unauthorized structures. Unlike in some other federal states, the Bavarian building authority can still take action against an unauthorized structure even decades later. The authority is bound by the principle of proportionality, but grandfathering does not automatically arise merely through the passage of time.

Frequently Overlooked Cases of Unauthorized Construction

In practice, we often encounter unauthorized construction in projects that owners mistakenly believe are exempt from permitting. According to the BayBO, many smaller projects in Bavaria are indeed exempt from the permitting process-but by no means all. Typical gray areas: garden sheds above a certain size (often 25 m³ gross volume or more), carports and garages with a floor area exceeding 50 m², solar systems on certain roof surfaces in historic preservation zones, terraces and terrace roofing with a depth exceeding 3 m, and change of use (e.g., office to apartment) without a change-of-use permit. If in doubt, you should always check with the building authority before starting construction-informal information is provided free of charge.

Legalization and Impact on Property Value

In many cases, an unauthorized structure can be legalized through a retroactive building permit. The prerequisite is that the structure complies with currently applicable building regulations-in particular the zoning plan, setback requirements, and fire safety standards. If this is the case, the owner can submit a regular building application and obtain the permit retroactively. The costs are often higher than for a regular permit, as supporting documents and expert reports must be submitted retroactively.

When purchasing real estate, an unauthorized structure poses a significant risk. If it is discovered only after the deed is executed, the seller may be liable for fraudulent misrepresentation. Buyers should therefore verify before the purchase that all construction work has been approved. A comparison of the actual building structure with the approved construction plans reliably reveals any discrepancies. Unlegalized unauthorized construction regularly leads to a depreciation of 15 to 30 percent, as banks do not include the affected areas in their mortgage lending value calculations.

Unauthorized Construction in a Purchase: Liability and Warranty

Anyone who purchases a property with an unauthorized structure that is not mentioned in the purchase agreement may assert warranty rights-provided that the material defect was not expressly excluded and the buyer was unaware of the unauthorized structure. In cases of fraudulent concealment by the seller, the exclusion of liability does not apply (Section 444 of the German Civil Code). Fraudulent concealment requires that the seller was aware of the unauthorized construction and deliberately concealed it.

For buyers, this means: Keep your eyes open when buying. If the seller demands a blanket exclusion of liability for construction defects, the buyer should review the construction files in advance and commission an expert. Questioning the seller about construction work requiring permits, documented in a contractual declaration, can also be helpful in the event of a dispute.

Practical Tip for Nuremberg and Franconia

In the Nuremberg metropolitan region, unauthorized structures are particularly common in established neighborhoods such as Gostenhof, Johannis, or Ziegelstein, where owners have been adding on to and renovating their properties for decades. Typical examples include unapproved sunrooms, converted attics, or garden sheds built later that do not meet the required setback distances from the property line. We recommend that buyers review the building file at the Nuremberg Building Authority before purchasing and compare the approved plans with the current condition. If any irregularities are found, we are happy to put you in touch with specialized real estate lawyers in the region.

Sellers should also address unauthorized structures before the sale. Open communication about measures requiring approval, combined with an attempt to legalize them, generally leads to a better sales outcome than a defect discovered after the fact-which regularly results in claims for price reductions or even rescission of the sale.

Frequently Asked Questions

Does an unauthorized structure become time-barred in Bavaria?

No, in Bavaria there is no statute of limitations under building law for unauthorized structures. The building authority can still intervene even after decades and issue a prohibition on use or an order to remove the structure. However, it must observe the principle of proportionality. The mere passage of time does not constitute formal grandfathering.

Can an unauthorized structure be retroactively approved?

Yes, provided the structure complies with currently applicable building regulations, a retroactive building permit may be applied for. To do so, the owner must submit a complete building application with all required documents. If the structure does not comply with the regulations, an exemption may be requested under certain circumstances-however, granting such an exemption is at the discretion of the authority.

What should I look for when buying a property to identify unauthorized structures?

We recommend reviewing the building file at the relevant building authority and comparing the approved plans with the actual condition of the building. Pay particular attention to retrofitted extensions, converted attics, and repurposed basement spaces. An experienced expert can quickly identify deviations and assess the chances of retroactive legalization.

What are the consequences of an unauthorized structure for financing?

Banks generally do not finance unauthorized structures, or only do so to a limited extent. Areas built in violation of permits are not taken into account when determining the mortgage lending value-which leads to a lower mortgage lending value and thus to worse loan terms or a higher equity requirement. In the case of existing financing, a discovered unauthorized construction may be considered a breach of contract if the bank assumed the property was in compliance with permits when granting the loan. We recommend always reviewing the building permit file before signing the purchase agreement when considering the purchase of existing properties.

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