
- 3 min read
- 06.11.2025
Attic: is your conversion approved?
Converting an attic is the most common way to gain living space throughout Germany. Often it is even the only option: in many cities, extensions can no longer be built due to lack of space.

Attic conversions, especially older ones, can cause problems if they were not approved under building regulations. Rapidly growing population numbers in the post-war period in the mid-20th century made it necessary to create housing quickly and with minimal red tape. Converting previously unused attic spaces was an obvious solution at the time. Today, however, this unconsidered approach is causing issues. One solution is obtaining retroactive approval.
Fire safety is a sensitive issue
If owners want to obtain retroactive approval for an unauthorized construction, the building regulations currently in force must be applied. These include setback requirements in relation to neighboring properties, new energy-efficiency standards, fire-safety regulations, accessibility rules, and—depending on the location—parking requirements that may mandate one parking space per apartment. As a result, securing retroactive approval for even a small attic apartment can become a massive undertaking. This deters many from taking action.
However, ignoring the issue is not a good idea. While overlooked requirements relating to energy efficiency or accessibility are not immediately life-threatening, inadequate fire protection can have dramatic consequences. Serious penalties can be imposed on owners if an attic space was converted without approval and without a second escape route—and a tenant consequently suffers harm. Owners should therefore address the retroactive approval of unauthorized construction sooner rather than later, despite the challenges.
Comprehensive advice for property owners
If you want to obtain retroactive approval for an attic conversion in your multi-unit building or are planning such a project, the advisors at Engel & Völkers Commercial can support you. They can also explain how an officially approved attic conversion can increase your property’s value and which additional measures may further enhance its value development.
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