They appear after the purchase and can cost a fortune. We explain what they are, who is liable and how to claim.
Buying & selling · Updated October 2026 · 5 min read
Hidden defects are serious property faults that were not visible at the time of purchase and that make it unfit for use or reduce its value: aluminosis, structural damp, illegal installations, pests…
The seller is liable for hidden defects even if unaware of them, within the legal period set by the Civil Code. If they knew and concealed them, liability is greater.
The best defence is prevention: a pre-purchase review and warranty clauses in the contract greatly reduce the risk.
The Civil Code sets a short period (six months for the warranty action), although depending on the case other routes with different deadlines may apply. It is advisable to act as soon as the defect is detected.
Yes, if it was not detectable during the viewing and affects habitability or safety. It is one of the most claimed structural defects in older buildings.
You can choose between rescinding the purchase, returning the property and recovering the price (redhibitory action), or a proportional reduction of the price (estimatory action), plus damages if the seller acted in bad faith.
The seller is liable under the warranty, even if an estate agent was involved. If they concealed the defect in bad faith, the claim is stronger and may include compensation for damages.
It helps, but doesn't guarantee it: the ITE assesses the general state of the building, not each dwelling. A technical survey of the specific property before signing the arras is advisable.
We analyse your case and claim from the seller the repair, a price reduction or the termination.
