Introduction
This study has been prepared to answer the question of whether changes can be made in the common areas of main immovable properties subject to condominium ownership, and according to what procedures and principles these changes should be carried out, in light of the decisions of the Supreme Court and the Council of State. The examinations are based on established case law shaped within the framework of the relevant articles of Law No. 634 on Condominium Ownership (KMK), particularly articles 19, 42, and 44. The study addresses fundamental issues such as the consent ratios required for changes in common areas, procedural differences according to the nature of the change, the role of zoning legislation, and the consequences of non-compliance with procedures.
Although judicial decisions primarily base their approach to changes in common areas on KMK Article 19, they have drawn a detailed framework for different situations arising in practice.
1. Required Majority Ratios: Distinction between Unanimity and Four-Fifths (4/5)
The Supreme Court considers the nature of the change to be made as the main criterion in determining the procedure to be applied.
Cases Requiring a Four-Fifths (4/5) Majority: Changes that do not create a substantial alteration in the project, do not affect the building’s structural integrity, and are generally beneficial fall under this scope. As stated in a decision by the 20th Civil Chamber of the Supreme Court, “…one of the flat owners cannot carry out construction, repair, installation, or alteration in the common areas of the main property without the written consent of four-fifths of all flat owners…” (2019/2176 E., 2019/4068 K.) is a general principle. Operations such as exterior facade insulation, chimney construction (provided it does not harm other owners), and the installation of simple facilities for common use in the garden can generally be carried out with this majority.
Cases Requiring Unanimous Consent: If the alteration affects the architectural integrity and project of the main property, unanimous consent is an absolute necessity. The General Assembly of Civil Chambers of the Supreme Court has clearly outlined this distinction: While 4/5 consent is sufficient for simple repairs, “substantial renovations are changes that alter the approved project of the structure and affect its architectural state. For such changes, a unanimous decision by all flat owners is required.” (2017/1996 E., 2022/5 K.). Examples of substantial renovations requiring unanimous consent include incorporating a balcony into a room, removing a partition wall to combine two independent sections, or integrating a common area such as the attic into an independent section. In a decision by the 5th Civil Chamber of the Supreme Court, it was ruled that the annulment of a decision to construct a staircase, which was contrary to the architectural project and required a renovation project, was appropriate because it was not taken with unanimous consent (2023/3152 E., 2023/8793 K.).
2. Binding Nature of Zoning Legislation and Official Institution Approvals
The agreement among property owners themselves does not override zoning rules concerning public order.
Insufficiency of Municipal Approval Alone: A renovation project being approved by the municipality does not mean that the consent of the property owners has been obtained, nor does it substitute for this consent. As emphasized by the 18th Civil Chamber of the Supreme Court of Appeals, “For a renovation project to be valid, mere approval by the municipality is not sufficient; the participation and consent of all owners of independent sections in the main property… must be present.” (2012/12421 E., 2013/3181 K.).
Violation of Zoning Legislation: Even if the change made receives the consent of all property owners, it is not legally valid if it violates zoning legislation. The 5th Civil Chamber of the Supreme Court of Appeals stated that a decision should be made to prevent the intervention found to be contrary to zoning regulations (2020/7796 E., 2020/9682 K.).
3. Effect of the Management Plan and Other Special Circumstances
Management Plan: The management plan, which regulates relations among property owners and is binding on all owners, can impose a unanimity requirement by making stricter the 4/5 majority ratio specified by law. The 5th Civil Chamber of the Supreme Court of Appeals emphasized in one of its decisions that the 4/5 ratio was raised to unanimity by the management plan, and therefore the consent of all owners should be sought (2024/11861 E., 2025/5590 K.).
Emergency Repairs: If a defect in common areas poses an imminent threat of damage to the main structure or an independent section, and repair is mandatory, the necessary intervention can be carried out by court order without seeking the consent of the floor owners (Supreme Court of Appeals 18th Civil Chamber, 2015/135 File No., 2015/12499 Decision No.).
Cooperatives: If a dispute arises in a cooperative structure, the matter is evaluated not only under the Condominium Law (KMK), but also within the framework of Law No. 1163 on Cooperatives and the principle of equality among cooperative members (Supreme Court of Appeals 16th Civil Chamber, 2008/5734 File No., 2009/6535 Decision No.).
Conclusion
It is possible to make changes in the common areas of main immovable properties subject to condominium ownership, but this process is subject to strict formal requirements and legal supervision. The procedure to be followed is determined by the nature of the change to be made. While a written consent of 4/5 of the floor owners is sufficient for simple repairs and installations that do not affect the architectural project; for substantial renovations that change the building’s architectural project, affect its structural integrity, or incorporate a common area into an independent section, a unanimous decision of all floor owners is mandatory. In both cases, it is essential that the change made complies with zoning regulations and adheres to any stricter provisions in the management plan. Changes made without adhering to these procedures will face the sanction of restoration to their original state by court order upon the request of other floor owners. A paper suggestion.
Why is an Expert Lawyer Necessary?
Modifications made in common areas in apartment or complex managements subject to condominium ownership are a legally quite technical matter. The determination of necessary majority ratios, the validity of municipal approvals, compliance with the project, and the consent requirements of the owners frequently become subjects of disputes and lawsuits. Therefore, especially in the rapidly developing construction processes in regions such as Çayırova, Tuzla, Pendik, Tepeören, Bayramoğlu, Mercan, Aydıntepe, Aydınlı, and Orhanlı, the professional support of an experienced lawyer in the field of condominium law is of great importance.
An Istanbul lawyer or a Çayırova condominium lawyer does not only apply Articles 19, 42, and 44 of the Condominium Law; but also guides their client through complex details such as compliance with zoning regulations, municipal approval, provisions of the management plan, and the distinction between unanimity and four-fifths majority. Incorrect decisions can lead to lawsuits for the cancellation and restoration of unlawful modifications made in common areas. In such cases, an expert condominium lawyer anticipates legal risks from the very beginning of the process, determines the correct strategy, and provides a solution between the parties either through settlement or litigation.
