Decennial Liability:Can Contractors/Engineers Deny Responsibility

Decennial Liability in Oman: Can Contractors or Engineers Deny Responsibility?

Construction projects in Oman are subject to a clear legal framework when it comes to structural defects and building failures. While this framework offers strong protection to employers, it also places significant responsibilities on contractors, designers, and supervising engineers. Recent court decisions show that this type of liability is applied in a strict way, sometimes going beyond traditional fault-based principles. 

Legal framework

Article 634 of the Omani Civil Transactions Law, together with Article 22 of the Law Regulating Engineering Consultancy Offices, establishes joint liability for contractors, engineers and designers for a period of ten years in relation to structural collapse or defects affecting safety.

This liability applies even where the defect is linked to soil conditions or site-related factors, and regardless of whether the parties are engaged under separate contracts.

Article 22 further clarifies that where a consultant’s role is limited to design only, liability is confined to design defects. It also confirms that any agreement seeking to exclude or limit this liability is invalid.

This liability arises by law and is intended to protect the employer and ensure the long-term safety of the project, regardless of how responsibilities are divided in practice.

Practical challenges and limits on denial defences

In practice, it is often difficult to deny responsibility when a claim is brought against more than one party, especially where the contractor, designer, and supervising engineer are all involved.

In such cases, it is not easy for any party to argue that the fault lies with another. This is particularly clear where defects relate to design or ground conditions. A contractor may argue that the works were carried out strictly in accordance with the approved design. However, the issue may still relate to technical judgment or site conditions. This argument is usually not enough when facing a claim from the employer. Courts allow the employer to claim against any of the responsible parties without first determining who caused the defect.

In other words, the distinction between design, supervision, and execution does not provide a defence at this stage. It only becomes relevant later, between the parties themselves.

This raises an important question: can a contractor avoid liability if they warned the employer about a design issue, or if the defect was not reasonably detectable?

We have not identified any published Omani judgment that addresses this point directly. However, in other jurisdictions such as Egypt, courts take a more detailed approach. A contractor may be relieved from liability for design defects if the design was provided by the employer. But this depends on certain conditions. The contractor will still be liable if they knew about the defect, or if it was obvious. On the other hand, liability may be avoided if the contractor clearly warned the employer and the employer insisted on proceeding.

Judicial approach

Omani courts have confirmed that decennial liability is applied strictly in practice. As they have made it clear that liability arises once a defect affecting safety is established. There is no need at that stage to prove who caused the defect.

In a Supreme Court judgment issued in 2021, the contractor argued that the defect was due to design and soil conditions and that it had merely executed the approved drawings. The Court rejected this argument. However, it stated that Article 634 creates a legal guarantee aimed at protecting the safety of the structure, which applies once the defect is proven, without the need to determine its source at that stage.

The Court also referred to Article 22, confirming that the different roles of design, supervision, and execution, even where carried out by separate parties , do not prevent joint liability towards the employer. At the same time, other decisions show that this joint liability does not settle how responsibility is shared between the parties. That issue is addressed later, based on each party’s role in causing the defect.

In practice, this is not always straightforward. Where the main dispute is subject to arbitration, it may not be possible to include all parties in the same proceedings. This can lead to multiple parallel proceedings, as well as issues relating to limitation periods and timing of recourse claims.

Why decennial liability leaves limited room for denial defences

The legal framework and court practice in Oman show that decennial liability is not mainly based on fault. It is designed to ensure the safety and stability of construction works.

As a result, it significantly limits the ability of contractors, designers, and supervising engineers to deny responsibility when facing a claim from the employer.

This does not mean that fault is irrelevant. Rather, its role is postponed to a later stage, when responsibility is allocated between the parties.

Conclusion

The legal framework and court practice in Oman show that decennial liability is mainly aimed at protecting the safety of buildings, which explains its wide scope in relation to all project parties. As a result, the ability to rely on denial defences is limited when facing a claim from the employer, especially where design, supervision, and execution roles overlap.

This does not remove the role of fault, but rather shifts it to a later stage, where responsibility is assessed between the parties based on their contribution to the defect.

In practice, this means that risk in construction projects should not be managed by relying on legal defences after a construction dispute arises, but by focusing on early technical review, proper coordination, and clear documentation throughout the project.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.