1. Direct Result

In light of legal regulations and literature data; an immovable property registered in the land registry as a “single independent section with an attic floor” (duplex), its actual use as two separate flats (e.g., closing the connection, opening a separate entrance) does not automatically change the legal nature of this property. In the urban transformation process (within the scope of Law No. 6306), sharing is, as a rule, not based on actual use, but is carried out based on the land share and number of independent sections in the land registry. The conversion of the de facto situation into two separate independent sections in a new project is only possible with the consent of all owners, compliance with zoning regulations, and a “Sharing Protocol” to be adopted by a 1/2 majority. Otherwise, individuals appearing as sole owners or co-owners in the land registry retain their entitlement corresponding to their existing land shares in the new project.

2. Conceptual Framework and Terminology

Attic Space (Piyesi): According to the Zoned Areas Development Regulation (Art. 40/7), independent sections cannot be constructed in attic spaces; these areas can only be built as interconnected spaces (piyes) with the independent sections on the top floor.

Independent Section: These are parts of the main real estate that are suitable for separate and independent use and are subject to independent ownership according to the provisions of the Condominium Law (KMK) 

Land Share: It is the co-ownership share allocated to independent sections in proportion to their values. It is the basic criterion for voting rights and share value in urban transformation 

Violation of Project: Closing the internal staircase of a unit appearing as a duplex in the approved architectural project and opening a separate entrance from the outside constitutes a violation of the obligation to “preserve the architectural integrity” within the scope of Condominium Law (KMK) Art. 19.

3. Main Approaches in Doctrine

Doctrine and established practice agree that the number of independent sections cannot be increased through actual use or physical interventions.

Principle of Legal Registration: For an area to be considered an independent section, it is not enough for it to be “suitable for independent use” ; this characteristic must be registered in the land registry.

Land Share Determinism: The biggest source of conflict in urban transformation is the land share. In accordance with Article 6 of Law No. 6306, decisions regarding the rebuilding of structures and sharing processes are made in proportion to the “land share rate” owned by the proprietors.

Emphasis on Location and Attributes: In sharing, not only the square footage but also the “location and attributes” of the immovable property should be taken into account. The goodwill value of an apartment with a roof annex differs from that of a standard apartment, and this should be reflected in CMB-licensed valuation reports.

4. Dissensions and Conflicts Among Approaches

Actual Situation vs. Title Deed Record: In practice, it is debatable whether properties actually used as two separate apartments will give rise to two distinct rights in urban transformation. While literature emphasizes the primacy of the title deed record, the “freedom of contract” dimension of urban transformation may allow owners, with a 1/2 majority, to develop a sharing model that recognizes the actual situation.

Fairness of Land Share: Some opinions argue that initial land shares were incorrectly determined (e.g., assigning a disproportionately high or low share to a duplex apartment due to its annex) and suggest filing a “land share correction lawsuit” before urban transformation.

5. Procedural Consequences and Impacts on Litigation Strategy

Correction of the Land Registry: If there is a legal error between the title deed record and the actual/technical reality, a lawsuit for the correction of the land registry may be initiated under Article 1025 of the Turkish Civil Code (TMK).

Restoration: Other flat owners can always file a lawsuit according to Article 19 of the Condominium Law (KMK) against the closure of the duplex’s connection. This situation is a risk factor before urban transformation.

Declaratory Lawsuits: Before demolition occurs, having the actual status (that it is used as two separate units) and the value of the property determined through a court constitutes evidence in future lawsuits for compensation or damages.

6. Substantive Law Consequences and Risk Areas

Administrative Sanctions: Since the de facto division is contrary to zoning legislation, there is a risk of demolition and a fine being imposed by the municipality in accordance with Articles 32 and 42 of the Zoning Law No. 3194.

Risk of Loss of Rights: If the owner of a property that appears as a single unit in the title deed is offered a single apartment in the new project, they cannot claim an additional right by asserting that they actually own two apartments. The legal basis is the land share.

Shared Ownership Issue: Those who own a duplex with a 1/2 share will continue to be co-owners of the independent unit allocated to them in the new project (unless otherwise agreed).

7. Inferences Applicable to the Specific Case

The following inferences can be made for the alternative situations specified by the user:

Scenario A: Person Residing on the Upper Floor is the Sole Title Deed Owner: This person is regarded as a single right-holder in urban transformation. The fact that they are actually using two apartments does not automatically entitle them to two apartments in the new project. However, if their land share is high, they can use this advantage with a valuation report to demand a larger or more valuable unit 2.

Scenario B: Person Residing on the Upper Floor is Not the Title Deed Owner: This person is in the position of a “possessor” or “holder of a personal right”. In urban transformation, the addressee is the title deed owner. A non-owner does not have a direct right to vote or demand in the sharing process; however, claims for compensation may arise based on the internal relationship between them and the owner (rent, usage permission, etc.).

Scenario C: De Facto Division by 1/2 Share Owners: If there are two co-owners with 1/2 shares each for a single independent section in the title deed, and they have de facto separated the lower and upper floors; in urban transformation, this unit is still considered as a “single unit”. For two separate apartments to be obtained in the new project, the land share must be large enough to accommodate two apartments. Otherwise, they will again be 1/2 share owners in the single apartment to be built.

8. Open Questions, Exceptions, and Uncertainties

Goodwill and Valuation: The extent to which the de facto use of the attic space as an independent apartment will be taken into account by CMB valuation experts within the “current situation value” is an area of uncertainty. Some experts consider the legal status (single apartment), while others base it on the current market value (potential for two apartments).

Municipal Practices: Some municipalities, in urban transformation projects, may permit the creation of an “additional independent unit” through zoning plan notes, considering the de facto situation; however, this is not a general rule.

9. Conclusion and Practical Assessment

The fundamental rule in the urban transformation of duplex apartments that include an attic floor (mezzanine) is **”the title deed record and land share basis”**is. De facto division does not grant legal status.

Practical Suggestions:

Sharing Agreement: Before transformation, a notarized “Sharing Agreement” should be made between the owners or shareholders of the de facto divided duplex, to clarify which apartment will belong to whom in the new building.

Land Share Control: If the land share has been unfairly determined due to the attic floor (mezzanine), a “Land Share Correction Lawsuit” should be filed before the building is demolished.

Project Approval: In the new architectural project, it must be confirmed with the municipality and the land registry office that the “independent unit requirements” (separate entrance, utilities, m2 criteria) are met, in order for two separate independent units to be registered in place of the old duplex.

Why is Expert Legal Support Necessary?

The urban transformation process for duplex apartments or apartments with an attic floor (mezzanine) involves much more legal complexity than that of a standard apartment. As 2M Hukuk Law Office, in the urban transformation consultancy processes we conduct on the Anatolian side of Istanbul — primarily in Tuzla, Pendik, Kartal, and Maltepe — this category is among the types of cases most frequently leading to loss of rights.

Loss of rights occurs unnoticed. In properties that appear as a single independent section in the title deed but are actually used as two separate flats, owners often assume they have the right to two flats. However, when the contractor delivers a single flat in the new project, the objection period has already passed. As a Tuzla lawyer, we have repeatedly observed that the only way to prevent these losses of rights is through a pre-contractual legal analysis.

The land share may have been determined unfairly. Due to the roof attic/mezzanine, land shares in some parcels were calculated incorrectly during the project phase: the area of the attic/mezzanine was sometimes included in the share, and sometimes not. If urban transformation is entered into without correcting this error, legally, a smaller or less valuable independent section might be offered in the new building. A lawsuit for the correction of land share filed before the demolition of the building eliminates this risk; however, a lawsuit filed after demolition is a much more difficult process with an uncertain outcome.

If the sharing protocol is not made on time, everything remains unresolved. In a scenario where two co-owners with 1/2 shares effectively divide the upper and lower floors — for example, in flats owned jointly by siblings or a mother and child — if a notarized sharing agreement is not made before urban transformation, the same joint ownership will continue in the new building. If this agreement is not made on time, future disputes will have to be taken to a lawsuit for the dissolution of co-ownership; this lawsuit can last for years. Within the scope of Istanbul urban transformation consultancy, preparing this agreement correctly closes off all future disputes from the outset.

The de facto division carries the risk of violating zoning regulations. Closing the internal connection of the duplex and opening a separate external entrance may lead to the risk of demolition and a fine under Articles 32 and 42 of the Zoning Law. Moreover, other floor owners can always file a lawsuit for restitution under Article 19 of the Condominium Law (KMK). This risk can become leverage for the opposing party during the urban transformation process. As part of our Istanbul urban transformation consultancy service within 2M Hukuk Avukatlık Ofisi (2M Law Office), we identify this risk before the process begins and prevent you from losing ground in negotiations with the contractor and other owners.

Scenarios A, B, and C require different legal paths. Whether you are the sole owner on the title deed, a 1/2 share partner, or your name is not listed on the title deed at all but you are actually living there — the legal path to follow, the court to apply to, and the evidence to be used are completely different for each of these three scenarios. If the wrong path is taken, in addition to loss of effort and time, there is also the risk of missing prescriptive periods.

In conclusion, the urban transformation process in apartments with attic floors or duplexes is a process that needs to be managed with an urban transformation lawyer from the beginning and requires much more foresight and technical knowledge compared to standard apartments. The Tuzla-based 2M Hukuk Avukatlık Ofisi (2M Law Office) provides urban transformation consultancy services in all districts of Istanbul’s European and Anatolian sides, including Pendik, Kartal, Maltepe, Ümraniye, Kadıköy, and Gebze.