Water Leakage and Waterproofing Defects in Turkiye: Contractor Liability under Turkish Law

Publication Date : November 2026

Water leakage and waterproofing defects in Turkey may give rise to legal claims involving defective construction, contractor liability and compensation for property damage. Water leakage, inadequate waterproofing and moisture intrusion are among the most common construction-related problems affecting residential and commercial properties in Turkiye. Following heavy rainfall, defects in roofs, terraces, balconies, exterior walls and drainage systems may become apparent, causing substantial damage to buildings and individual properties.

Such problems raise an important legal question: Who is responsible for construction defects, and what legal remedies are available to property owners under Turkish law?

The answer depends on the nature of the defect, the contractual relationship between the parties and the applicable legal framework.

1.Water Leakage and Waterproofing Defects in Turkey: Common Construction Defects

Under Turkish law, construction defects generally arise when completed works fail to comply with contractual specifications, applicable technical standards or the characteristics reasonably expected from the completed work.

Common examples of waterproofing and construction defects include improper installation of waterproofing membranes, inadequate roof or terrace insulation, defective drainage systems, insufficient sealing around windows and balconies, and improper construction techniques resulting in water penetration.

However, not every instance of water leakage automatically constitutes a construction defect.

The underlying cause must be established through an assessment of the building's condition, construction specifications, maintenance history and relevant technical evidence.

Distinguishing between defective workmanship and damage resulting from inadequate maintenance is particularly important when determining legal responsibility.

2. Contractor Liability under the Turkish Code of Obligations

Contractors may be held liable for defective construction works under Articles 470 et seq. of the Turkish Code of Obligations (Law No. 6098). Article 475 establishes certain legal remedies available to the party entitled to exercise rights arising from a defective construction contract.

Depending on the contractual relationship and the circumstances of the case, these remedies may include the following.

Repair of Defective Works:

Where the statutory requirements are satisfied, the client may request that construction defects be remedied at the contractor's expense, provided that the necessary repairs do not entail disproportionate costs.

In cases involving water leakage or inadequate waterproofing, this may include repairing defective insulation, correcting drainage deficiencies or eliminating construction-related causes of water penetration.

Reduction of the Contract Price:

Where legally appropriate, a party entitled to remedies under a construction contract may retain the completed work and request a proportionate reduction in the contract price due to defective workmanship.

The availability of this remedy depends on the contractual relationship, the nature of the defect and the applicable statutory requirements.

Compensation for Damages:

The client may also be entitled to claim compensation for additional losses arising from defective construction under the applicable provisions of Turkish law. Such losses may include damage to interior finishes, flooring, furniture or other property affected by water penetration, provided that the relevant legal requirements for compensation are satisfied.

Importantly, the legal position of a purchaser who has acquired ownership of a completed property may differ from that of a party to the original construction contract.

A subsequent purchaser's rights against the seller or contractor must therefore be assessed separately, taking into account the relevant contractual arrangements and applicable legal provisions.

3. Liability for Roof and Common Area Defects

Water leakage originating from roofs, common terraces, exterior structural elements or shared drainage systems may also involve the Turkish Condominium Law (Law No. 634).

Under Article 4 of the Condominium Law, roofs, common roof terraces and rain gutters are generally classified as common areas. Consequently, responsibility for maintenance and repair may fall within the obligations of condominium owners and building management. Articles 19 and 20 of the Condominium Law establish relevant obligations concerning the maintenance, preservation and repair of common areas.

However, responsibility for maintaining common areas should not be confused with liability for defects arising from the original construction. Where water leakage results from defective workmanship or inadequate waterproofing during construction, potential contractor liability must be examined separately. Determining whether the damage originates from construction defects, maintenance failures or subsequent alterations is therefore essential.

4. Notification Requirements and Limitation Periods

Turkish law establishes specific requirements concerning the inspection of completed works, notification of defects and limitation periods. Under Article 474 of the Turkish Code of Obligations, the client must inspect the completed work as soon as reasonably practicable following delivery and notify the contractor of identified defects within an appropriate period.

Article 477 further provides that defects discovered after delivery must generally be notified to the contractor without delay upon discovery.

Failure to comply with the applicable notification requirements may adversely affect the exercise of rights arising from defective workmanship.

Under Article 478, claims arising from defective construction works involving immovable structures are generally subject to a five-year limitation period commencing from delivery. Where the contractor is responsible for gross fault, a twenty-year limitation period may apply.

Nevertheless, different legal relationships, including property sales and consumer transactions, may be governed by additional or different requirements.

Accordingly, the applicable limitation period and notification obligations must be determined by reference to the legal nature of the particular dispute.

5. The Importance of Technical Evidence

In construction defect disputes, technical evidence frequently plays a decisive role in establishing liability. Water leakage may result from several different causes, including defective construction, inadequate maintenance, structural deterioration or modifications undertaken after completion. Identifying the actual cause is therefore essential before determining the responsible party. Relevant evidence may include construction contracts, architectural and technical specifications, photographs, expert assessments, correspondence between the parties and records of repair expenses.

Where appropriate, obtaining a court-supervised expert examination before substantial repairs are undertaken may be particularly important for preserving evidence.

However, urgent measures necessary to prevent further damage or protect building safety should not be unnecessarily delayed.

A comprehensive technical and legal assessment can help establish the existence of a defect, identify the responsible parties and determine the remedies available under Turkish law.

6. Legal Considerations for Foreign Property Owners in Turkey

Foreign individuals and companies owning residential or commercial properties in Turkiye may encounter construction defects after purchasing or taking possession of a property.

In such cases, the available legal remedies depend on several factors, including the contractual relationship with the seller or contractor, the nature of the transaction, the date of delivery and the circumstances in which the defect was discovered.

The transfer of a title deed does not automatically establish that every remedy arising from the original construction contract is directly available against the contractor.

Depending on the circumstances, claims may instead arise under the provisions governing property sales, defective performance or other applicable legal grounds.

Foreign property owners should therefore obtain an assessment of the relevant contracts and technical evidence before initiating legal proceedings.

Conclusion

Water leakage and waterproofing defects can result in substantial financial losses and complex legal disputes involving contractors, property owners, sellers and condominium management. Turkish law provides several mechanisms for addressing defective construction works, including repair, price reduction in appropriate circumstances and compensation claims. However, determining the responsible party and the available legal remedies requires careful consideration of the contractual relationship, technical evidence, notification requirements and applicable limitation periods. Early identification of construction defects and timely legal assessment can play an important role in protecting property owners' rights and preventing further damage.

Alper Law Office advises clients on construction defects, contractor liability and real estate disputes under Turkish law.