Property encroachment: when a building overhangs the neighbour's land

Imagine yourself in Barentin, in your garden, enjoying a morning coffee. Looking up, you see the party wall separating your property from your neighbour's. Suddenly, you notice that for a few months, a small concrete block extension has been protruding a few centimetres onto your land. Nothing too serious, you think. But legally, this advance of a few centimetres could cost you dearly – or bring you a lot. How should you react? The question every owner asks is: can I demand the demolition of this encroaching part, even if it is minimal? The answer is clearly yes, and the Court of Cassation firmly reminded us of this in a judgment of 26 June 1979.

In this decision, the high court ruled that Article 555 of the Civil Code (which allows the landowner to keep constructions built on their land by a third party, subject to compensation) does not apply when the builder has encroached on the neighbouring land. In other words, even if the encroachment is ridiculously small, the owner of the invaded land can demand the demolition of the protruding part. Neither the minimal importance of the encroachment nor the good faith of the builder can oppose this request. It is a rule of implacable severity, but protective of the right of property.

Concretely, this case law means that you are not obliged to suffer an encroachment, even a modest one. But be careful: it does not give you a blank cheque to demand anything. The court will verify the reality of the encroachment and may, in some cases, prefer damages to demolition if the latter would cause disproportionate harm. However, the principle remains that the aggrieved owner has the choice. Let us examine together the facts of this case and what it changes for you.

The facts: a story that happens every day

The case that gave rise to this judgment involves two owners in a classic context of party wall construction. Mr X, an owner in Barentin, had undertaken extension works to his house. By mistake or negligence, he caused his foundations and part of the wall to protrude onto the neighbouring land belonging to Mr Delord. The latter, noticing the encroachment, demanded the demolition of the encroaching part. Mr X opposed this, arguing that the encroachment was minimal (barely a few centimetres) and that he was in good faith. He invoked Article 555 of the Civil Code to offer compensation to his neighbour, rather than demolish.

The dispute was brought before the tribunal de grande instance of Rouen. At first instance, the judges ruled in favour of Mr Delord: they ordered the demolition of the part of the construction resting on the neighbouring land, despite its minimal importance. Mr X appealed. The Court of Appeal of Rouen upheld the judgment, adopting the reasons of the first judges. Mr X then appealed to the Court of Cassation, arguing that Article 555 of the Civil Code should apply and that demolition could not be ordered without taking into account good faith and the triviality of the encroachment.

But the Court of Cassation dismissed his appeal. It held that Article 555 does not apply when a builder extends his works beyond the boundaries of his own land. No matter the extent of the encroachment: if the owner of the neighbouring land demands demolition, it must be ordered. This solution is firm and leaves little room for manoeuvre for the clumsy builder. The message is clear: before building, scrupulously check the boundaries of your land.

The reasoning of the court — dissected

To understand the decision, you must first grasp what Article 555 of the Civil Code says. This article governs the fate of constructions built by a third party on another's land. In principle, the landowner can choose to keep the construction by paying compensation to the builder (if the builder was in good faith) or demand its demolition. But the Court of Cassation specifies here that this text does not apply when the builder exceeds the boundaries of his own land. Why? Because the builder did not build entirely on another's land: he built on his own land but spilled over onto the neighbouring land. The situation is different, and the aggrieved owner can invoke the protection of his right of property, based on Article 544 of the Civil Code (right to enjoy and dispose of one's property in the most absolute manner).

The judges' reasoning is also based on the general principle of civil tort liability, now codified in Article 1240 of the Civil Code (which obliges reparation for damage caused by one's fault). By encroaching, the builder commits a fault that causes harm to the neighbouring owner. This harm consists of the very infringement of the right of property. The Court of Cassation affirms that demolition can be ordered "when the owner of that land demands it, despite the relatively minimal importance of the encroachment". In other words, the request for demolition is a discretionary right of the owner: he does not have to justify a particular harm; the encroachment itself is already harm.

What few people know is that this solution is not new. It is part of constant case law. The Court of Cassation had already ruled, in earlier judgments, that encroachment, even minimal, justifies demolition. The 1979 judgment confirms this strict line. The judges did not want to create an exception for small encroachments, as this would open the door to abuse and weaken the right of property. However, note: if demolition would cause manifestly disproportionate harm to the builder (for example, destroying an entire building for a 2 cm encroachment), the judge could, in a spirit of balance, prefer to award damages. But this is the exception, not the rule.

What this changes for you — concretely

This case law has very concrete practical implications, depending on your profile. If you are a landlord and your tenant undertakes works without authorisation, you can demand the demolition of any encroachment onto the neighbouring land. But be careful: you could also be liable vis-à-vis the neighbour if you do not stop the encroachment. As a tenant, you must know that any improvement that exceeds the boundaries of the land can expose you to an action for demolition, even if you are in good faith. As a buyer of a property, check before buying that no construction protrudes onto the neighbouring land: an undeclared encroachment can be held against you after the sale.

Let's take a concrete example. Imagine you are an owner in Petit-Quevilly. Your neighbour has built a garden shed that protrudes 15 cm onto your land. You can demand the demolition of that part. The cost of demolition will be borne by the neighbour, responsible for the encroachment. If you do nothing, you risk, over time, losing the ability to act (30-year limitation period, or shorter if the construction is for residential use – 10 years). If you sell your house, the buyer could turn against you for failure to disclose.

If you are in this situation, you must act quickly. Send a formal notice to your neighbour by registered letter with acknowledgement of receipt, demanding the removal of the encroachment within 30 days. If nothing happens, take the matter to the tribunal judiciaire. The procedural costs (lawyer, expert) can be high (expect between €2,000 and €5,000 for a first instance), but demolition is generally ordered. An alternative solution: negotiate an agreement, for example a right of way or a transfer of the encroached plot. But this depends on the goodwill of the parties.

Four tips to avoid this type of dispute

• Have a boundary survey carried out by a chartered surveyor before any construction. This is the only way to know with certainty the boundaries of your land. The cost (approximately €1,500 to €2,500) is modest compared to demolition costs and damages.
• If you buy a property, require a planning certificate and a topographical survey. Check that existing constructions do not protrude onto neighbouring land. In case of doubt, ask for a warranty clause in the deed of sale.
• In case of a construction project, inform your neighbours by registered letter. Explain your plans and seek their written agreement. This helps prevent disputes and, if a neighbour objects, find an amicable solution before investing.
• If a neighbour starts work likely to encroach, intervene immediately. A simple letter or visit may be enough to stop the encroachment. Do not let the situation drag on: each passing day makes demolition more difficult and costly.

Further reading: related case law and developments

The solution of the 1979 judgment is not isolated. It is part of constant case law of the Court of Cassation. For example, in a judgment of 27 February 2008 (n° 07-10.568), the Court held that encroachment, even minimal, constitutes an infringement of the right of property and that demolition can be ordered without the builder being able to invoke Article 555. More recently, in a judgment of 12 July 2018 (n° 17-19.489), the same court specified that demolition is not automatic if it causes disproportionate harm to the builder, but this exception is very rarely applied.

The courts' tendency is therefore firm: the protection of the right of property prevails over the good faith of the builder. The lower courts (tribunaux d'instance, tribunaux judiciaires) apply this rule strictly. What this means for the future: if you plan to build, make sure you do not encroach, even by a few millimetres. New technologies (GPS, drones) allow very precise surveys, and chartered surveyors are increasingly in demand. In case of dispute, proving the encroachment is easier, which further strengthens the position of the aggrieved owner.

What you must absolutely remember

FAQ:

1. My neighbour has built a wall that encroaches 5 cm onto my land. Can I demand demolition? Yes, absolutely. The Court of Cassation allows it, regardless of the size of the encroachment.
2. Do I have to pay for the demolition? No, the builder must bear the cost of demolition, as it is he who committed the fault.
3. What if the encroachment is very old (over 30 years)? The action for demolition may be time-barred. If the encroachment has lasted more than 30 years, your neighbour may invoke adverse possession (usucapion) and become owner of the strip of land. Consult a lawyer without delay.
4. Can I claim damages instead of demolition? You can, but the judge is not obliged to award them. If demolition is possible, it will be preferred. If it is impossible or disproportionate, the judge may award damages for the harm suffered.
5. Do I have to go through a lawyer? Yes, for court proceedings before the tribunal judiciaire, representation by a lawyer is mandatory. For a simple formal notice, you can do it yourself.

Are you in a similar situation? A first 30-minute consultation with Maître Zakine (€45) could save you months of proceedings — and often much more. Book an appointment →