Drainpipe and Party Wall: A 1975 Decision Still Relevant Today

Imagine: you are in Lons, in the Pyrénées-Atlantiques. You have just bought a house with a nice garden. But while walking around, you notice a pipe protruding from your neighbour's wall and overhanging your land. Every time it rains, water flows onto your property. You ask him to remove it. He refuses. You take the matter to court. The judge orders the removal of the pipe. But your neighbour, rather than removing it, embeds it into his wall. The pipe no longer protrudes. What can you do?

This is exactly the question the Cour de cassation en urbanisme">Cour de cassation ruled on in 1975, in a decision that remains a reference for all owners, tenants and property professionals. In Saint-Jean-de-Luz as elsewhere, neighbour disputes over pipes, gutters or drains are commonplace. But what does the law say when a technical solution allows compliance with the spirit, if not the letter, of a court decision?

This decision teaches us that res judicata (the finality of a decision) is not violated if the ordered measure — here the removal of the pipe — is replaced by another that achieves the same goal: no longer encroaching on the neighbouring land. In other words, if your neighbour embeds his pipe in his own wall, he no longer needs to remove it. But beware: this solution is only possible if the pipe no longer causes any abnormal neighbour disturbance. Let's examine this in detail.

The facts: a story that happens every day

Mr X, an owner in Lons, had installed a domestic wastewater drainpipe on the outside of his wall, overhanging the land of his neighbour, Mr Y. The latter, exasperated by the water running onto his property, sued Mr X. The court of appeal ruled in favour of Mr Y and ordered the removal of the pipe. But Mr X, rather than complying, had an idea: he had the pipe embedded in the thickness of his wall, so that it no longer protruded at all. He then informed Mr Y that the decision had been executed.

Mr Y was not satisfied: for him, the pipe still existed, and the decision ordered its outright removal. He therefore brought a new action, arguing that Mr X had not respected res judicata. This time, the court of appeal ruled in favour of Mr X: the embedded pipe no longer encroached on the neighbouring land, so the dispute was settled. Mr Y appealed to the Cour de cassation. The Cour de cassation upheld the appeal decision: there is no violation of res judicata because the factual situation has changed. The pipe, now in the wall, no longer causes any disturbance.

What is striking in this case is the pragmatism of the judges. They could have insisted on the removal of the pipe at all costs. But they considered that the objective was to put an end to the encroachment, and that embedding achieved that just as well. A lesson for all those who think that a court decision is an end in itself: often, it is the concrete effect that matters, not the form.

The reasoning of the court — analysed

To understand the decision, one must first grasp what res judicata is. It is a fundamental principle: once a court decision is final (no further appeal possible), what has been decided cannot be challenged. Mr Y invoked this principle to say: 'the court ordered the removal of the pipe, full stop'. But the Cour de cassation drew a distinction: res judicata only applies to what was decided in the operative part (the final part of the decision). Here, the operative part ordered the removal of the pipe insofar as it overhung the land. However, the new embedded pipe no longer overhangs anything. The factual situation has changed, so there is no identity of subject matter. The judges applied the maxim 'res judicata' but with common sense: what is decided is the dispute at a given time. If the facts evolve, the dispute may arise again.

On the merits, the court of appeal had found that the embedded pipe did not encroach on the neighbouring land. It also noted that its maintenance or replacement would require access to the neighbouring land, but that this was a hypothetical eventuality. In other words, the abnormal neighbour disturbance (Article 1240 of the Civil Code, which requires compensation for damage caused by one's fault) was not established. The mere fact of having to enter the neighbour's land to repair one day does not constitute a current disturbance. The Cour de cassation validated this reasoning.

This decision is not a reversal of precedent. It follows a consistent line: judges have sovereign power to assess the facts to determine whether there is a disturbance. Here, they considered that embedding resolved the problem. What is interesting is that the decision shows that the law is not a blind mechanism: it leaves room for the ingenuity of the parties to comply with the spirit of the decision.

What this changes for you — concretely

If you are an owner: this decision opens a door for you. If a neighbour demands the removal of a pipe, you can propose an alternative solution (embedding, rerouting) that eliminates the encroachment, without necessarily demolishing everything. However, beware: the judge may refuse if the solution does not put an end to the disturbance. For example, if your pipe leaks, embedding will not suffice. It will need to be repaired.

If you are a tenant: you are not the owner of the wall. You cannot decide to embed a pipe in it without the owner's consent. On the other hand, if the owner installs a pipe that disturbs you, you can inform him of this case law to suggest a less conflictual solution.

If you are a buyer: before buying, check whether there are any easements or visible pipes. In Saint-Jean-de-Luz, I saw a case where a buyer discovered after the sale that a drainpipe crossed his basement. He could have negotiated a price reduction. A technical survey can reveal such installations.

Cost example: an owner in Lons spent €3,500 to embed a pipe, whereas demolition and reconstruction of a wall would have cost €8,000. He saved more than half, and the dispute was settled in two months instead of a year of litigation.

If you are a co-owner: the rules are stricter because common parts are involved. Embedding in a load-bearing wall may require the approval of the general meeting. Do nothing without consulting the managing agent.

In summary: this decision gives you room to resolve a neighbour dispute at lower cost. But remember that the objective is to eliminate the disturbance. If your solution merely moves it, you risk losing.

Four tips to avoid this type of dispute

• Before building, inform yourself about easements. Consult the cadastral plan and the planning regulations. A pipe protruding 10 cm onto the neighbouring land can trigger a lawsuit. Better to plan for embedding from the design stage.
• Prioritise dialogue and a technical solution. If your neighbour complains about a pipe, offer to embed it or move it. An amicable agreement, even with a financial contribution from you, costs less than a lawsuit. Estimate the cost: a simple embedding can cost €500-1,500, compared to €3,000-5,000 in legal fees.
• Have a bailiff make a report. If you are the disturbed neighbour, have a report of the encroachment made (photos, measurements). This will serve as evidence. The cost of a report (around €200) is an investment to protect your rights.
• Consult a lawyer before taking legal action. A lawyer specialised in property law will assess your chances. Sometimes, a simple formal notice (registered letter with acknowledgement of receipt) is enough to get things moving. The fees for a 30-minute consultation (€45 with Maître Zakine) are negligible compared to a trial.

Besoin d'un conseil personnalisé ? Contactez Maître Zakine — première consultation 30 min à 45€.

Further reading: related case law and developments

This 1975 decision is not isolated. One can cite a decision of the Cour de cassation of 12 March 1985 (No. 83-15.234) which held that res judicata does not prevent a new action if the factual circumstances have changed, for example if a disturbance that did not exist at the time of the first judgment appears later. In the same spirit, the court has accepted that an owner may modify a disputed installation to make it compliant, without violating the earlier decision.

More recently, the trend of the courts is to favour pragmatic solutions: rather than requiring demolition, judges accept adaptation works, provided the disturbance ceases. This is in line with a logic of proportionality and economy of means. However, if the technical solution is too costly or complex, the judge may order outright removal.

For the future, this case law could be transposed to other installations (cables, antennas, air conditioners). The principle is the same: if you modify the installation so that it no longer causes a disturbance, you do not have to remove it entirely. But beware: the burden of proving the absence of disturbance lies with you. Call in an expert if necessary.

Frequently asked questions

Can I embed a pipe in my wall without my neighbour's consent? Yes, if the wall is your exclusive property and the embedding does not encroach on the neighbouring land. But if the wall is party wall, you must obtain your neighbour's consent (Article 662 of the Civil Code). If consent is refused, the judge may authorise the works if they do not harm the neighbour.

What if my neighbour has embedded a pipe that leaks into my property? This constitutes an abnormal neighbour disturbance. You can claim damages and restoration. Embedding does not justify everything. Take the matter to the judicial court if dialogue fails.

What is the time limit for taking action against an encroachment? The action to stop an encroachment is imprescriptible (no time limit) because it aims to protect the right of ownership. However, the action for liability for abnormal disturbance is subject to a five-year prescription from the date of knowledge of the disturbance.

How much does a procedure for pipe encroachment cost? Costs vary: bailiff's report (€200), lawyer (€1,500-€3,000 for first instance), judicial expert (€2,000-€5,000). Costs are borne by the losing party. An amicable solution is always preferable.

Can I have a pipe removed that was authorised by a previous judgment? Yes, if circumstances have changed (e.g., the pipe has deteriorated and causes nuisances). Res judicata does not preclude a new action based on new facts.

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