What Is the Defects Liability Period (DLP) in Construction?
The Defects Liability Period (DLP) is the time after completion, set in the contract, during which the contractor must return to correct defects in the works at its own cost. It typically starts on the date stated in the taking-over certificate, and ends when the contractor has fixed all notified defects.
What the contractor must do in the DLP
During the period the employer or its representative notifies defects, and the contractor must correct them within a reasonable time or the time the contract sets. If the contractor does not, the employer may have the work done by others and recover the cost, often from retention or a bond. Defects caused by misuse or normal wear are not the contractor's responsibility.
Length and extension
The length is fixed by the contract, and common features are:
- A stated number of months from the date of taking over, often 12 months, though it varies.
- Different periods for different parts, such as specified systems or sections.
- An extension for works that were defective and had to be made good, according to the contract.
DLP, retention and final acceptance
At the end of the period, and once defects have been corrected, the employer issues a final or performance certificate. The remaining retention is normally released at that point or the contractor's bond is returned. It is worth keeping a clear defect log, because the end of the period only comes once all notified defects are closed.
DLP on Gulf projects
Gulf contracts usually state the defects liability period in the contract data or particular conditions. This contractual period is separate from any statutory liability for structural defects under local law, which lasts longer and varies by jurisdiction. Ask your legal adviser how the two interact on your project.
How Arkan supports the defects period
A clear defect log is the main working tool in this period, and Arkan provides one.
- Punch lists track defects from discovery through resolution and closure, with photos, comments and an activity timeline.
- Items can be assigned and viewed on a Kanban board, and exported to CSV or PDF.
- NCRs record significant non-conformances with corrective action and verification.
Frequently asked questions
What is the full form of DLP in construction?
DLP stands for Defects Liability Period. FIDIC contracts call a similar period the Defects Notification Period.
How long is a typical DLP?
It is set by the contract. Periods differ between projects and between parts of the works, so read the contract data rather than assume a standard length.
What is the difference between DLP and warranty?
The DLP is the contractual period to correct defects. A warranty is a separate assurance, often from a manufacturer or specialist, that may last longer.
When does the DLP start?
Normally on the completion date stated in the taking-over certificate, or the date of practical completion in other contract forms.
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Last updated: 2026-10-14. Definitions are general guidance. Your contract and project procedures govern.
