What Is a Defects Liability Period in Construction in Turkey (2026): Duration, Latent vs Patent Defects, Retention Release & Enforcement

Understanding what is a defects liability period in construction is essential for every developer, contractor and in-house counsel operating in Turkey’s building sector. The defects liability period (DLP) is the contractually defined window, beginning on practical completion or formal handover, during which the contractor remains obligated to identify and remedy defects in the completed works. In Turkey, DLP durations typically range from 12 months for straightforward building projects to 24–36 months for complex engineering works, though public-procurement contracts governed by Law No. 4735 may impose significantly longer statutory liability windows.

As market participants across Turkey undertake contract risk reviews in 2026, grasping the mechanics of DLP clauses, the distinction between latent and patent defects, the release of retention and defects liability bank guarantees, and the available enforcement routes, from Yargıtay litigation to ICC and ISTAC arbitration, has never been more commercially important.

What Is a Defects Liability Period? Legal Nature and When It Starts

A defects liability period in construction is a fixed timeframe, stipulated in the construction contract, during which the contractor bears the obligation to rectify defects that emerge in the completed works at no additional cost to the employer. It is not a creation of statute alone; rather, it arises primarily from the parties’ agreement, with its legal underpinning rooted in the Turkish Code of Obligations (Law No. 6098), which governs contracts for work (eser sözleşmesi) and sets out the employer’s right to demand repair of defective performance.

Under Turkish law, the DLP clock typically starts running from the date of provisional acceptance (geçici kabul) or practical completion, the point at which the employer takes possession of the works and begins using them, even if minor snagging items remain outstanding. The contract should specify whether the trigger is provisional acceptance, issuance of a completion certificate, or some other milestone. In public-procurement contracts, the provisional acceptance protocol is governed by the Public Procurement Contracts Law (Law No. 4735) and its implementing regulations, which set formal procedural requirements for the acceptance commission’s approval.

Practical Completion vs Final Acceptance

These two concepts serve different legal functions in Turkish construction practice:

• Practical (provisional) completion (geçici kabul). The works are substantially complete and fit for their intended use. The DLP begins here. A completion certificate or protocol is issued, and the contractor’s primary performance obligation is treated as fulfilled, subject to defects remediation.
• Final acceptance (kesin kabul). Issued after the DLP expires, once all notified defects have been remedied and the employer (or, in public works, the acceptance commission) confirms that the works conform to the contract. Final acceptance triggers the release of remaining retention and defects liability bank guarantees.

Industry observers note that disputes frequently arise when contracts fail to define the precise trigger date for the DLP. Best practice is to include explicit language tying the DLP start date to a defined event, typically the date appearing on the provisional acceptance certificate, and to require both parties to sign off on that date within a stated number of days.

How Long Does a Defects Liability Period Typically Last in Turkey?

The defects liability period duration is not fixed by a single statutory rule; it depends on the contract type, the complexity of the works, and whether the project falls under private or public procurement rules.

Standard Industry Durations

For private-sector construction contracts in Turkey, the following defects liability period durations are common market practice:

• Simple building projects (residential, standard commercial fit-outs): 6–12 months from provisional acceptance.
• Complex engineering or infrastructure projects (power plants, highways, tunnels): 24–36 months from provisional acceptance.
• FIDIC-based contracts (widely used on international projects in Turkey): the Defects Notification Period under FIDIC 2017 Red Book defaults to 12 months but is routinely extended by the Particular Conditions to 24 months for infrastructure works.

The Turkish Code of Obligations (Law No. 6098) does not prescribe a mandatory minimum DLP for private contracts. Parties enjoy broad contractual freedom to agree on the period that suits the risk profile of the project. However, clauses that attempt to exclude defects liability entirely are likely to be unenforceable as contrary to the mandatory provisions on the employer’s inspection and notification duties under the same statute.

Public Procurement Exceptions

Public works contracts governed by Law No. 4735 operate under a different regime. The implementing regulations typically require a minimum DLP (often referenced in the contract’s special conditions), and the contractor’s statutory liability for defects in an immovable work (yapı eseri) is subject to longer prescription periods under Law No. 6098. For defects caused by gross negligence or intentional concealment, the limitation period can extend significantly beyond the contractual DLP, a point frequently tested before the Yargıtay (Court of Cassation). The likely practical effect of the public procurement framework is that contractors on government projects must maintain their financial capacity and guarantee instruments for substantially longer than on private works.

Latent vs Patent Defects, Detection, Notice and the Latent Defects Liability Period

Not all construction defects are visible at handover. Turkish law and standard contract practice distinguish between patent defects and latent defects, and the distinction has critical implications for limitation periods and the enforceability of claims.

• Patent (apparent) defects. Defects that are, or should be, discoverable upon reasonable inspection at the time of provisional acceptance. Under the Turkish Code of Obligations (Law No. 6098), the employer must inspect the works and notify the contractor of apparent defects within a reasonable time. Failure to do so may result in the employer being deemed to have accepted the works as conforming.
• Latent (hidden) defects. Defects that could not have been detected through a reasonable inspection at handover and that only manifest during subsequent use, for example, concealed waterproofing failures or structural reinforcement shortfalls. The latent defects liability period under Turkish law is not capped by the contractual DLP. Instead, the employer’s right to claim persists for the statutory limitation period prescribed by Law No. 6098, running from the date of discovery of the defect.

Limitation Timeline for Defects Claims

Early indications from recent Yargıtay practice suggest that courts take a strict approach to the employer’s notification duty: even for latent defects, unreasonable delay in notifying the contractor after discovery can weaken or extinguish the claim. In-house counsel should implement a protocol for immediate written notification upon discovery, including photographic evidence, expert reports where available, and a clear description of the defect.

Drafting Defect Liability Period Clauses in Turkey, Best Practice and Red Flags

A well-drafted defect liability period clause is the single most important contractual tool for managing post-completion risk. Poorly drafted clauses generate ambiguity, delay enforcement, and expose both parties to unnecessary litigation.

Essential Elements of a DLP Clause

Every defect liability period clause in a Turkish construction contract should address the following elements:

• Trigger date. Define when the DLP commences, typically the date of the provisional acceptance certificate (geçici kabul tutanağı).
• Duration. State the DLP length in months. Specify whether different durations apply to different work packages (e.g., mechanical and electrical systems may warrant longer periods than civil works).
• Scope of obligation. Clarify whether the contractor’s obligation is to repair, replace, or re-execute defective work, and whether consequential costs (e.g., access, temporary works) fall to the contractor.
• Notification procedure. Require the employer to notify defects in writing within a stated number of days of discovery, specifying the defect, its location, and the requested remedy.
• Re-triggering provision. Specify whether the DLP for a repaired element restarts from the date the repair is completed. This is common in FIDIC-based contracts and strongly recommended.
• Defect liability period certificate. Require issuance of a formal certificate at DLP expiry confirming that all notified defects have been remedied, triggering final acceptance and release of security.

Sample DLP Clause (Abridged)

The Defects Liability Period shall commence on the date stated in the Provisional Acceptance Certificate and shall expire [12/24] months thereafter. During this period, the Contractor shall, at its own cost and within [14] days of receiving written notice from the Employer, remedy any defect in the Works that is attributable to defective materials, workmanship or design (to the extent design is the Contractor’s responsibility). Where the Contractor remedies a defect during the Defects Liability Period, the period for the remedied element shall restart and run for a further [12/24] months from the date on which the remedy is completed and accepted by the Employer.

Upon expiry of the Defects Liability Period and completion of all outstanding remedial works, the Employer shall issue a Defects Liability Certificate, and the Contractor’s remaining retention and/or defects liability bank guarantee shall be released within [28] days thereof.

Red Flags to Avoid

• Silent on re-triggering. If the clause does not state whether the DLP restarts after a repair, a dispute is almost inevitable.
• No sectional DLP provision. Where works are handed over in sections, each section should have its own DLP start date. A single blanket date can leave early-delivered sections unprotected or over-protected.
• Excluding latent defects. Any clause purporting to exclude the contractor’s liability for latent defects is likely unenforceable under Turkish law, given the mandatory statutory protections in Law No. 6098.

Securing DLP Obligations, Retention, Bank Guarantees and Insurance

Contractual obligations during the defects liability period are only as strong as the security that backs them. Turkish construction practice relies on three principal mechanisms to ensure the contractor performs its remedial obligations: retention, defects liability bank guarantees, and insurance.

How Each Security Type Works

Retention Release, Practical Steps

Releasing retention is one of the most contentious post-completion processes in Turkish construction. Industry observers expect the following procedural sequence to minimise disputes:

1. Pre-expiry inspection. Conduct a joint inspection of the works no later than 30 days before DLP expiry. Compile a final snagging list.
2. Remediation. The contractor remedies all items on the snagging list within the contractual notice period (typically 14–28 days).
3. Defects liability certificate. The employer (or, for public works, the acceptance commission) issues the defects liability period certificate confirming that all defects have been remedied.
4. Release instruction. The employer issues a written release instruction to the paying bank or, in the case of retention, processes the payment within the number of days stated in the contract (commonly 28 days).

For construction projects under public procurement, the release of the defects liability bank guarantee is subject to formal final acceptance (kesin kabul) procedures set out in the implementing regulations of Law No. 4735. The guarantee cannot be released until the acceptance commission has completed its review and the final acceptance protocol has been signed.

Enforcement in Turkey, Notice, Rectification and Dispute Resolution

When defects emerge and the contractor fails or refuses to remedy them, the employer must follow a structured enforcement path. Turkish law provides both contractual and statutory remedies, and the choice of dispute resolution forum, courts or arbitration, has significant practical implications.

Step-by-Step Enforcement Checklist

1. Formal written notice. Serve a detailed notice on the contractor identifying the defect, its location, the contractual basis for the claim, and a deadline for rectification (matching the period specified in the defect liability period clause).
2. Contractor’s rectification right. Under the Turkish Code of Obligations (Law No. 6098) and most standard-form contracts, the contractor has the first right to remedy. The employer should allow the contractor reasonable access and time to carry out repairs.
3. Self-help / third-party remedy. If the contractor fails to rectify within the stipulated period, the employer may engage a third party to carry out the repairs and recover the cost from the contractor, either by drawing on the defects liability bank guarantee, deducting from retention, or pursuing a claim.
4. Dispute resolution. If costs cannot be recovered through the security instruments, or if the parties disagree on the existence or scope of a defect, the matter proceeds to the contractually agreed dispute resolution mechanism.

Courts vs Arbitration

Turkish courts with jurisdiction over construction disputes include the commercial courts of first instance (asliye ticaret mahkemeleri). The Yargıtay (Court of Cassation) acts as the appellate authority and has developed a substantial body of case law on construction defects, limitation periods and the employer’s notification obligations. However, most internationally influenced Turkish construction contracts include arbitration clauses referring disputes to the Istanbul Arbitration Centre (ISTAC) or the ICC International Court of Arbitration. Arbitration awards, whether domestic or foreign, are enforceable in Turkey under domestic enforcement legislation and, for foreign awards, under the New York Convention (to which Turkey is a signatory).

For construction lawyers in Turkey, the practical recommendation is to ensure that the defect liability period clause and the dispute resolution clause operate in tandem: notice periods, evidence preservation requirements, and escalation timelines should be internally consistent. A mismatch between the DLP notification window and the pre-arbitration negotiation period is a common drafting error that can delay enforcement.

Practical Checklists and Templates for DLP Management

Effective management of the defects liability period in construction requires disciplined documentation from the date of provisional acceptance through to final acceptance and security release. The following checklist is designed for project managers, in-house counsel and external advisors.

DLP Management Checklist

• At provisional acceptance: Confirm DLP start date in the signed provisional acceptance certificate. Photograph all areas of the works. Record the snagging list with signatures from both parties.
• During the DLP: Log every defect report in a defects register (date, description, location, photographs, contractor response). Issue written notices within the contractual deadline. Track contractor response times against the defect liability period clause requirements.
• Before DLP expiry: Schedule a joint inspection at least 30 days before expiry. Issue the final snagging list. Confirm that re-triggered DLP periods for previously repaired items have been separately tracked.
• At DLP expiry: Issue the defects liability period certificate (or request the acceptance commission to do so for public works). Prepare the retention release or bank guarantee return instruction. File all records for post-DLP latent defect claims.

Sample Defect Notification Letter, Key Content

• Contract reference and DLP clause number.
• Date of discovery of the defect.
• Precise location (building, floor, element reference).
• Description of the defect with photographic evidence attached.
• Contractual deadline for rectification (state the number of days and the expiry date).
• Statement that, absent timely rectification, the employer reserves the right to engage a third party and recover costs from retention or the defects liability bank guarantee.

Maintaining a complete document pack, including the defects register, all notices sent and received, inspection reports, and photographic records, is critical. This evidence is routinely requested by arbitral tribunals and Turkish courts when adjudicating defects claims, and incomplete records are frequently cited by the Yargıtay as a basis for weakening an employer’s position.

Conclusion

The defects liability period in construction is far more than a contractual formality, it is the primary risk-allocation mechanism governing post-completion quality assurance in Turkey. Whether you are drafting a new contract, managing a live DLP, or enforcing a defects claim, the interplay between the defect liability period clause, Turkish statutory obligations under Law No. 6098, and the available security instruments demands careful, jurisdiction-specific analysis. As market participants across Turkey review and renegotiate their contract frameworks in 2026, getting the defects liability period right, from duration and drafting to retention release and enforcement, will determine whether construction disputes are resolved efficiently or become prolonged and costly.

Sources

1. Turkish Code of Obligations (Law No. 6098), TBMM
2. Turkish Official Legislation Portal, Mevzuat.gov.tr
3. Public Procurement Law (Law No. 4734), Kamu İhale Kurumu
4. Court of Cassation (Yargıtay), Official Portal
5. Union of Turkish Bar Associations
6. Turkish Civil Code (Law No. 4721), Council of Europe Translation