Roof Encroachment: 20 cm Enough to Demand Demolition (Cass. 3e civ., 10 Nov. 2016)

Imagine the scene: you are the owner of a house in Caen, in the quiet neighbourhood of Pierre Heuzé. One day, you notice that your neighbour's roof, freshly renovated, overhangs your land by 20 centimetres. Nothing serious, you think? No leak, no apparent damage. Yet you feel that your property right has been violated. You ask your neighbour to move his gutter; he refuses, arguing that the encroachment is minimal and without consequence. What to do? Go to court? That seems disproportionate for twenty centimetres… But the law is clear: your right of property is absolute. This decision of the Court of Cassation of 10 November 2016 forcefully reminds us of this.

In this judgment, the highest judicial court censured a court of appeal which had refused to order the demolition of a 20 cm encroachment, on the grounds that it would be disproportionate. The Court of Cassation reaffirmed that Article 545 of the Civil Code prohibits any encroachment on another's land, whatever its extent. A victory for the property owner, but also a warning for careless builders.

But what does it actually change for you, whether you are a property owner in Falaise or a tenant in Caen? Quite a lot. This article breaks down the case, explains the judges' reasoning, and gives you practical advice to avoid or manage such a dispute. Because an encroachment, even of a few centimetres, can cost you dearly if you suffer it… or if you commit it.

The facts: a story like many that happen every day

The case pits the [M] family, owners of a house in Caen, against the [V] family, their neighbours. During renovation work on the roof of the [V]'s building, it turns out that the new roof encroaches onto the [M]'s property by about 20 centimetres. More specifically, the roof overhangs the party wall, encroaching on the air and soil of the neighbouring property.

The [M]s sue the [V]s to obtain the demolition of the encroaching part. At first instance, the court rules in their favour and orders demolition. But the [V]s appeal. The Caen Court of Appeal, in a judgment of 26 March 2015, reverses the decision: it finds that the encroachment is only 20 centimetres, that it has caused no disorder or damage, and that its rectification would be detrimental to both parties and disproportionate. In short, it considers that it is not worth the candle.

The [M]s do not give up and appeal to the Court of Cassation. They argue that the owner of a property on which another owner's construction encroaches is entitled to demand its demolition, without having to prove damage. The Court of Cassation agrees with them on 10 November 2016, quashing the appeal judgment and remanding the case to the Rouen Court of Appeal.

In other words, the lower court judges (the Court of Appeal) had tried to introduce a notion of proportionality, but the Court of Cassation reminded that the right of property is absolute: any encroachment, even minimal, must be removed at the simple request of the aggrieved owner.

The reasoning of the court — broken down

The decision of the Court of Cassation is based on Article 545 of the Civil Code, which provides: "No one may be compelled to transfer his property, except for public utility purposes and upon payment of a fair and prior indemnity." In plain language, no one can force you to let someone else use your land, even a tiny bit. The Court concludes that any encroachment, no matter how minimal, constitutes a violation of the right of property and entitles the owner to demand the demolition of the encroaching construction, without having to show actual damage (concrete harm).

What few people know is that the lower court judges had tried to apply a principle of proportionality, inspired by the case law of the European Court of Human Rights (ECHR). They thought that destroying a roof for 20 cm was excessive. But the Court of Cassation firmly rejected this approach: the right of property prevails over any consideration of balance or good neighbourliness.

The [V]s' arguments – absence of disorder, disproportionate cost – were swept aside. The Court considered that once the encroachment is established, the owner has an absolute right to demolition. It is not a mere option; it is an obligation for the judge to order the reinstatement.

Note, however, that this solution is not new. The Court of Cassation has applied constant case law since the "encroachment" decision of 1999 (Civ. 3e, 4 May 1999, No. 97-14.966). But the 2016 judgment has the merit of reminding that lower court judges cannot invoke proportionality to dismiss the claim. In short, the Court of Cassation locks the system: no compromise possible.

What this changes for you — concretely

This decision has very practical implications, whether you are a property owner, tenant or real estate professional.

If you are the owner of an encroached property: You can demand the demolition of the encroaching part, even if the encroachment is tiny (a few centimetres) and without damage. Concrete example: in Falaise, you discover that your neighbour's terrace overhangs your plot by 15 cm. You can ask him to demolish it, and if he refuses, sue him. The judge must order demolition, without being able to consider cost or minor importance. However, note that this action is subject to a 30-year limitation period (time to act). But if the encroachment is recent, act quickly.

If you are the owner of a property that encroaches: You are in danger. Even if the encroachment is "minimal", you may be forced to demolish at your own expense. In my practice, I have seen cases where a simple gutter overhang of 10 cm led to costly proceedings. Before building or renovating, have a land survey (precise delimitation of property boundaries) carried out by a chartered surveyor. Cost: around €1,500 to €2,500, but this can save you a demolition costing several thousand euros.

If you are a tenant: You are not directly concerned, but you must report any encroachment you observe to your landlord (owner). It is up to him to act. If you suffer an encroachment (e.g., a neighbouring roof overhanging your balcony), inform your landlord in writing.

If you are a buyer: Before buying, check the property boundaries and any encroachments. An amicable boundary survey with the neighbour can be included in the suspensive conditions of the sale agreement. If an encroachment exists, you can either require its regularisation before the sale or renegotiate the price.

In summary, this case law is a powerful weapon for aggrieved owners, but a serious risk for those who build without precaution.

Four tips to avoid this type of dispute

• Have a land survey done before any construction or renovation. A chartered surveyor precisely delimits property boundaries. This document serves as evidence in case of dispute. Cost: €1,500 to €3,000 depending on the area. In Caen, expect around €2,000 for a standard plot.
• Include a boundary survey clause in your sale agreement. If you are buying, make the boundary survey a suspensive condition (a condition without which the sale does not go ahead). Thus, if an encroachment is discovered, you can withdraw or negotiate.
• Photograph and document any encroachment as soon as you discover it. Take photos with a tape measure, note the date, and send a registered letter to your neighbour to record the encroachment. This will serve as evidence in court.
• Consult a solicitor before starting proceedings. A simple formal notice (registered letter with acknowledgement of receipt) may be enough to make the neighbour back down. But if the conflict persists, a solicitor specialising in property law will help you obtain a quick decision. Avoid using a conciliator: in this type of dispute, mediation is often ineffective because the law is very clear.

Further reading: related case law and developments

This decision is part of a consistent line of the Court of Cassation. As early as 1999, in the "encroachment" decision (Civ. 3e, 4 May 1999, No. 97-14.966), the Court held that "the owner of a property on which a construction has encroached is entitled to demand its demolition, without having to prove damage." The 2016 judgment merely confirms and clarifies this rule.

But another decision deserves mention: the "Party Wall" decision of 2014 (Civ. 3e, 12 February 2014, No. 12-25.045) where the Court accepted that if the encroachment is caused by a party wall, the situation is different: the owner of the wall may be forced to tolerate a minimal encroachment if it results from normal use of the party wall. So be careful not to confuse: encroachment on private non-party wall land is always penalised.

The trend of the courts is therefore very protective of the right of property. Lower court judges sometimes try to soften the rigour of the rule, but the Court of Cassation calls them to order. For the future, it is unlikely that the case law will evolve, because the right of property is a fundamental right guaranteed by the Constitution and the ECHR.

If you are faced with an encroachment, know that justice is on your side, provided you act within the time limits (30 years from the encroachment) and provide evidence of the encroachment (boundary survey, photos, bailiff's report).

Key points to remember

FAQ:

1. Can I demand the demolition of an encroachment of only 5 cm?
Yes. The Court of Cassation has confirmed it: any encroachment, even minimal, justifies demolition, without any condition of damage.

2. What if my neighbour refuses to demolish?
Send him a formal notice by registered letter with acknowledgement of receipt. If he persists, apply to the Judicial Court (formerly the High Court) for a demolition order. You can also ask for a daily penalty (astreinte) to compel him.

3. Are there any exceptions?
Yes, if the encroachment results from a party wall (normal use of the party wall) or if the encroachment is due to an easement (right of way, etc.). But in most cases, the rule is absolute.

4. What are the time limits for taking action?
The action for demolition is subject to a 30-year limitation period from the completion of the encroaching construction. After this period, you can no longer demand demolition, but you can claim damages.

5. How much does a procedure cost?
Solicitor's fees vary: expect €1,500 to €3,000 for a first-instance procedure, plus expert costs (surveyor, bailiff). The court summons costs about €150. But if you win, the neighbour may be ordered to reimburse part of your costs (Article 700 of the Code of Civil Procedure).

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