The defects liability period is the period after practical completion during which the contractor is responsible for returning to site to correct defects that become apparent.
It is a standard provision in most UK construction contracts, including JCT contracts, and typically lasts between 6 and 12 months depending on the project.
The defects liability period ensures the building performs as intended after handover, while giving the client protection against issues that were not evident at completion.
How the Defects Liability Period Relates to Practical Completion
The defects liability period begins immediately after practical completion has been certified.
At this point, the client takes possession of the building, and responsibility for day‑to‑day operation shifts away from the contractor.
You can read more about this milestone in our guide to practical completion.
While the building is now usable, the defects liability period provides a formal mechanism for addressing any issues that arise once the building is occupied.
How Long Does the Defects Liability Period Last?
The duration of the defects liability period is set out in the construction contract and will vary depending on the nature and complexity of the project.
- Typically 12 to 24 months on most UK construction projects
- May be longer for complex or high‑risk developments
- Different elements of the works may have different liability periods
At the end of this period, a final inspection is usually carried out to confirm all defects have been addressed before final completion is certified.
Client vs Contractor Responsibilities
Understanding responsibilities during the defects liability period is essential to avoiding disputes and ensuring issues are resolved efficiently.
Client Responsibilities
- Notify the contractor of defects when they become apparent
- Allow reasonable access for inspection and remedial works
- Operate and maintain the building correctly
Contractor Responsibilities
- Return to site to rectify defects within a reasonable time
- Carry out remedial works in accordance with the contract
- Ensure defects are properly resolved rather than temporarily fixed
These responsibilities are typically administered by the Employer’s Agent or Contract Administrator, who oversees the process and ensures contractual procedures are followed.
How Defects Are Managed
Defects are usually identified through inspections, client feedback or operational issues once the building is in use.
- A defects list (or snagging list) may be maintained
- The contractor is instructed to return and rectify items
- Works are inspected to confirm if the defect has been resolved
- Outstanding issues are tracked until completion
Proper tracking and documentation are important to ensure nothing is missed before the final certificate is issued.
Common Risks During the Defects Liability Period
While the defects liability period provides protection, there are still risks if it is not managed properly.
- Failure to report defects: If not formally recorded, issues may not be addressed before the period expires
- Disputes over responsibility: Disagreements may arise over whether defects are due to design, workmanship or use
- Poor contractor response: Delays in returning to site can affect building performance
- Incomplete records: Lack of documentation can weaken the client’s position
- Loss of leverage: Once the period ends, it becomes harder to require corrective works
Active contract administration helps minimise these risks and ensures defects are resolved properly before final completion.
Why the Defects Liability Period Matters
The defects liability period provides an important safeguard for clients, ensuring the quality of construction can be verified after the building is occupied.
It also gives contractors an opportunity to correct issues while maintaining their contractual obligations.
For organisations new to development, understanding how this period works is essential to protecting the long-term performance and value of a project.
Need Support Managing Defects and Handover?
BuildAlliance provides structured support during practical completion and the defects liability period through Employer’s Agent & Contract Administration and Project Management.
Discuss Your Project