When a contractor fails to perform construction or other agreed work properly, the first legal question is not always simply whether “the work is defective.”

Turkish law distinguishes between defective work and incomplete work.

That distinction can affect notice requirements, the legal remedies available and the way the claim should be proved.

What is a contract for work?

Article 470 of the Turkish Code of Obligations regulates the contract for work, or eser sözleşmesi.

Under this type of contract:

  • the contractor undertakes to create a work, and
  • the employer undertakes to pay the agreed price.

The concept is broader than the construction of an entire building.

Depending on the circumstances, it can include:

  • renovation;
  • fit-out work;
  • roofing;
  • electrical installations;
  • mechanical installations;
  • manufacturing of a specific product;
  • machinery work;
  • repair and maintenance;
  • technical installations; and
  • other projects where a particular result is promised.

What is incomplete work?

Incomplete work exists where the contractor agreed to perform a particular part of the work but did not perform it at all.

Examples may include:

  • insulation required by the contract was never installed;
  • a specified room or section was left unfinished;
  • agreed equipment was never installed;
  • part of the electrical work was omitted;
  • landscaping included in the contract was never carried out; or
  • a contractual item appearing in the bill of quantities was simply not performed.

The Court of Cassation has long distinguished incomplete work from defective work.

In 15th Civil Chamber E.2014/5163, K.2015/3868, the Court explained that defective work concerns a deficiency in the qualities of work that was performed, whereas incomplete work concerns work which the contractor undertook to perform but did not perform.

Why does the distinction matter?

The distinction has practical procedural consequences.

The special defect-notification rules applicable to defective performance do not necessarily apply in the same manner to work that was never performed.

Court of Cassation case law has recognized that the price or cost associated with incomplete work may be claimed within the applicable limitation period without being subject to the same defect-notification requirement imposed for defective work.

A party should therefore not automatically classify every problem on a construction site as an “ayıp.”

What is defective work?

Defective work exists where the contractor performed the work, but the finished work does not possess:

  • the characteristics agreed in the contract; or
  • the qualities it should objectively possess.

Examples can include:

  • a roof was completed but leaks;
  • waterproofing was applied but is ineffective;
  • flooring was installed but begins cracking;
  • the wrong quality of material was used;
  • windows were installed but do not close properly;
  • installed equipment does not meet the technical specification; or
  • a repaired system still fails to function as promised.

A defect may be apparent at delivery or may be hidden and emerge only later during use.

What must the employer do after delivery?

Article 474 of the Turkish Code of Obligations requires the employer, after delivery, to inspect the work as soon as reasonably possible according to the ordinary course of events.

If defects are discovered, they must be notified to the contractor within an appropriate period.

Ignoring an obvious defect for a long period can therefore create legal problems.

The employer should ordinarily document the defect and give notice in a form that can later be proved.

Depending on the dispute, useful evidence may include:

  • email;
  • notarized notice;
  • registered electronic communication;
  • delivery records;
  • photographs;
  • video;
  • site records; and
  • expert inspection.

Can the work be inspected by an expert?

Yes.

Article 474 also allows either party, at its own expense, to request that the work be examined by an expert and that the findings be recorded in a report.

In a serious construction dispute, technical evidence can be more important than witness recollections.

The precise location, dimensions and cost of a defect may later become impossible to determine once repairs begin.

What rights does the employer have for defective work?

Article 475 provides several alternative remedies where the contractor is responsible for the defect.

Depending on the seriousness and circumstances of the defect, the employer may:

1. Terminate or rescind the contract

Where the work is defective to such a degree that the employer cannot use it or cannot reasonably be required to accept it, the employer may have the right to withdraw from the contract.

This is not available for every minor defect.

The severity of the defect and the nature of the work matter.

For work constructed on the employer’s land, the statutory rules also restrict rescission where removal of the work would cause disproportionate damage.

2. Keep the work and request a price reduction

The employer may retain the work and request a reduction in the contract price proportionate to the defect.

This remedy can be particularly relevant where the work remains usable but has lower value because it does not satisfy the contract.

3. Require free repair

Where repair would not result in disproportionate expense, the employer may require the contractor to correct the defect at the contractor’s cost.

The proportionality of the repair cost may become an expert issue.

4. Claim damages

Article 475 also preserves the employer’s right to claim damages under the general provisions where the requirements for damages are satisfied.

The appropriate claim therefore depends not only on the existence of a defect but also on its seriousness, repairability, cost and consequences.

Can the employer hire someone else to repair the problem immediately?

Care is required.

In some cases immediate third-party intervention may be necessary, particularly where delay would cause additional damage or create safety risks.

However, commercial construction and technical-service agreements frequently contain:

  • warranty clauses;
  • notice periods;
  • cure periods;
  • contractor access requirements; and
  • procedures requiring the original contractor to be given an opportunity to repair.

If the employer ignores those procedures and immediately gives the work to another contractor, a later claim for the full repair cost may become more difficult.

The contract should therefore be reviewed before third-party repair work begins wherever circumstances allow.

A recent example of the importance of contractual repair and warranty procedures can be seen in Court of Cassation 6th Civil Chamber E.2025/2878, K.2026/2077 dated 13 May 2026.

Why is court-supervised evidence preservation important?

Construction defects frequently change over time.

For example:

  • a leak may be repaired;
  • cracked plaster may be removed;
  • a defective pipe may be replaced;
  • incomplete work may later be completed;
  • another contractor may alter the original construction; or
  • damaged material may be discarded.

Once this happens, it can become difficult to prove what the original condition was.

For that reason, a party may seek delil tespiti, or judicial preservation/determination of evidence, before or during the dispute.

A court-appointed technical expert may examine issues such as:

  • which items are missing;
  • which items are defective;
  • whether the work complies with the project;
  • what materials were used;
  • the severity of the defect;
  • whether repair is technically possible;
  • the cost of repair;
  • the cost of completing omitted work; and
  • the effect on the value of the project.

For higher-value construction disputes, this can become one of the most important pieces of evidence in the later lawsuit.

What documents should be preserved?

A construction claim should rarely be assessed only by looking at the signed contract.

Relevant material may include:

  • contract and amendments;
  • technical specifications;
  • architectural and engineering drawings;
  • bill of quantities;
  • quotations;
  • progress-payment certificates;
  • invoices;
  • payment records;
  • delivery and acceptance records;
  • site diaries;
  • meeting minutes;
  • inspection records;
  • emails;
  • WhatsApp messages;
  • photographs and videos;
  • subcontractor documents; and
  • expert reports.

For commercial contractors, contemporaneous written records are often far more useful than trying to reconstruct events months later.

What is the limitation period for defective work?

Article 478 contains specific limitation rules for claims arising from defective work.

The ordinary periods run from delivery.

They are generally:

  • two years for works other than immovable structures;
  • five years for immovable structures; and
  • twenty years where the contractor is grossly at fault, regardless of the type of defective work.

The applicable category must be determined according to the nature of the work and the claim.

Does a five-year limitation period mean the employer can wait five years before notifying the defect?

No.

The limitation period and the defect-notification requirement are separate issues.

A claim may technically be within the limitation period but still face problems because an apparent defect was not inspected and notified within the period required under Article 474.

This is why waiting until shortly before expiry of the limitation period can be dangerous.

What about hidden defects?

A defect may not be discoverable through an ordinary inspection at delivery.

Problems such as hidden waterproofing failures, concealed installation defects or structural issues may emerge later.

The timing of discovery, the nature of the defect and the subsequent notification then become important.

The employer should document when the problem first appeared and when the contractor was notified.

What is the practical difference between an incomplete-work claim and a defective-work claim?

Suppose a contractor agreed to install ten items.

If only eight were installed, the missing two are generally an incomplete-work issue.

If all ten were installed but three fail to satisfy the agreed specification, the issue is generally defective work.

In a real construction file both may exist simultaneously.

A project can contain:

  • unpaid contractor receivables;
  • incomplete items;
  • defective items;
  • delay claims;
  • contractual penalties;
  • additional-work claims; and
  • set-off or deduction claims

at the same time.

Correctly categorizing each item can materially affect the litigation strategy.

Sources: Turkish Code of Obligations No. 6098, Articles 470 and 474–478; Court of Cassation 15th Civil Chamber E.2014/5163, K.2015/3868, 01.07.2015; Court of Cassation 15th Civil Chamber E.2012/319, K.2012/950, 20.02.2012; Court of Cassation 6th Civil Chamber E.2025/2878, K.2026/2077, 13.05.2026.

This article provides general information on Turkish law. The contract, technical specifications and condition of the work must be assessed individually.