The Italian Supreme Court of Cassation, with the recent order no. 17028/2025, has redefined the existing boundaries between the so-called “construction defects” and “incorrect design choices”, revising the different liabilities between the builder and the contractor of the works.

As is well known, both cases entitle the buyer to compensation for the damage suffered.

Article 2055 of the Italian Civil Code, by virtue of the principle of so-called “joint and several liability”, provides that if the harmful event is attributable to multiple persons, all of them are jointly liable for compensation. Therefore, in the event that the damage results both from poor design and incorrect execution of the works, the designer, the builder and even the works director are jointly liable towards the buyer / client for the damages suffered.

The most important innovation introduced by the aforementioned order of the Court of Cassation is represented by the extension of the warranty right also to design defects, which is not forfeited even when the buyer has reviewed or formally approved the designs prior to the purchase.

On this point, the Supreme Court holds that the buyer is not necessarily required to possess the technical expertise to assess any design errors.

Therefore, the buyer has the full right to take action against the designer and the worksdirector for contractualbreach, benefiting from a ten-year limitation period.

In order not to lose the rights related to the warranty, it is necessary:

• for ordinary defects (Art. 1667 Italian Civil Code), discrepancies, imperfections, lack of quality that, however, do not compromise the work, to report the issue within 8 days from discovery; legal action must be initiated within one year from the delivery of the property;
  
• for serious defects (Art. 1669 Italian Civil Code), defects that negatively affect the structural or functional elements of the property. The warranty lasts ten years from the completion of the works and the claim must be filed within one year from discovery. In most cases, the date of the claim coincides with that of the technical report by a professional (Architect, Engineer, Surveyor).
  

By construction defects, we mean defects in manual or technical execution by the builder or the contractor in the construction of a property, or the noncompliance of the latter with the contractual agreements entered into.

The most common construction defects may include: errors in the installation of materials; defects in finishing; lack of waterproofing … etc.

Incorrect design choices, on the other hand, concern deficiencies in the execution of the agreed works/ activities which, although carried out in compliance with the original design, are unsuitable/not functional to ensure the normal use of the property.

Common examples include inadequate thermal or acoustic performance due to incorrect technical choices, incorrect assessment of the soil on which the structure will be built, incorrect sizing of systems.

In the above cases, liability is attributable to the contractor, even when the works have been carried out on the basis of a third party’s design. Among the duties of the contractor, in fact, there is also the obligation to report any errors contained in the design that may prejudice its proper execution.

The buyer of a property, therefore, benefits from specific protections in relation to construction defects and incorrect design choices.

The legal actions that may be taken are listed below:

1. elimination of defects, the buyer is entitled to have any defects remedied at the builder’s expense;
   
2. price reduction, in order to retain ownership of the property, paying a fair amount corresponding to its actual condition;
   
3. compensation for damages, the buyer is always entitled to obtain compensation for the damages suffered, including those resulting from the unavailability of the property during any restoration works;
   
4. termination of the contract, as a last resort, this solution may be pursued where the detected defects render the property unsuitable for use or significantly reduce its value.
   

If you find yourself in this situation, my firm can offer an initial case assessment. Do not hesitate to contact me to evaluate together the best strategy to protect your interests.