Party Wall in a Condominium: When a Co-owner Can Act Alone for Common Parts

Imagine: you own a flat in Nanterre, in a condominium built in the 1970s. For months, dampness has been rising through the wall of your living room. The diagnosis is clear: the party wall with the neighbouring garden is in poor condition. But this wall is a common part of the condominium. Who must act? The managing agent, the general meeting, or can you bring an action yourself? This is the question that the Court of Cassation settled in 1984, in a judgment that remains a reference for all co-owners.

The answer is simple and powerful: yes, you can act alone, without the authorisation of the managing agent, if you suffer personal damage. This decision, handed down on 6 March 1984 (appeal no. 82-16.759), laid down a clear principle: damage to the common parts, of which each unit includes a share, constitutes for each co-owner personal damage authorising him or her to seek compensation, both for the collective disturbance and for his or her individual harm.

But what exactly does this change for you? How should you react if you are in this situation? Let us delve into this landmark decision, which I break down for you, with concrete examples from my practice in Nanterre, Versailles and elsewhere.

The facts: a story like those that happen every day

The case began in a condominium building, one of whose walls was a party wall with a garden belonging to a lady, whom we shall call Mrs Y. The wall in question, which supported the entire building, deteriorated over the years. Water seepage appeared in the units of several co-owners. One of them, Mr X, owner of several units in the building, decided to act. He sued Mrs Y before the Nanterre High Court to obtain a complete reconstruction of the party wall.

Mrs Y defended herself by arguing that Mr X had no standing to act alone: the wall was a common part of the condominium, and only the managing agent or the general meeting of co-owners could bring an action on behalf of all. In short, she argued that Mr X could not claim works that would benefit all co-owners without their consent. Did the Nanterre court agree with her? Not exactly.

The court examined the situation. It noted that the party wall served a different function for each co-owner: for some, it was simply a boundary wall; for others, it supported their flat. The deterioration of the wall caused seepage into Mr X's units, which constituted personal damage. However, the court held that the deterioration was due to Mrs Y's fault, as she had not maintained the wall on her side. On the other hand, it refused to order a complete reconstruction of the wall, considering that this would go beyond Mr X's personal damage and encroach on the rights of the other co-owners.

Mr X appealed to the Court of Cassation. The Court of Cassation, in its judgment of 6 March 1984, quashed the lower court's decision: it affirmed that damage to the common parts, of which each unit includes a share, constitutes for the co-owner personal damage authorising him or her to seek compensation for both collective and personal disturbances. In other words, Mr X could demand the complete reconstruction of the wall, even if it benefited everyone, because he suffered individual harm.

The reasoning of the court — broken down

To understand this decision, one must examine the judges' reasoning. The Court of Cassation relied on Article 1240 of the Civil Code (formerly Article 1382), which provides that "any act of a person which causes damage to another obliges the person by whose fault it occurred to make reparation". This general principle of civil liability is the foundation of the action.

Next, the Court recalled that the common parts belong to all co-owners undividedly. Each unit includes a share of these common parts. Thus, when a common part is damaged, each co-owner suffers an infringement of his or her property right, even if the damage is shared. This damage is both collective (all co-owners suffer from the deterioration) and personal (each co-owner may see his or her unit affected, for example by seepage).

The Court dismissed Mrs Y's argument that only the managing agent could act. It considered that the co-owner has a personal interest in acting, distinct from the collective interest. What few people know is that this solution was not obvious: before 1984, some courts required that the managing agent be the only one able to sue in respect of common parts. This decision therefore marked a jurisprudential turning point.

Note, however, that the Court did not call into question the role of the managing agent. The managing agent retains day-to-day management, but the co-owner may act in parallel if his or her damage is personal. undefined that Mr X could demand the complete reconstruction of the wall, even if other co-owners did not wish to incur costs. The Court thus protected the individual right of each co-owner not to passively suffer deterioration.

What this changes for you — concretely

This decision has very concrete implications for co-owners, landlord owners, and even tenants. Here is how it applies in everyday life.

For the occupying co-owner: if you notice seepage, cracks or any other damage originating from a common part (roof, façade, load-bearing wall, etc.), you can take legal action against the person responsible (a neighbour, a third party, or even the managing agent if he or she fails to act). You do not need to wait for a general meeting. For example, in Versailles, a co-owner obtained an order against her neighbour to repair a common terrace that was leaking into her flat, based on this judgment.

For the landlord owner: if your tenant reports defects originating from a common part, you, as a co-owner, can act directly without going through the managing agent. But note: you must prove your personal damage (for example, loss of rent if the property becomes uninhabitable). undefined, I have encountered cases where landlords obtained damages for loss of enjoyment.

For the tenant: you are not a co-owner, but you can inform your landlord of the problem. The landlord can then act. You can also take action yourself against the owner of the wall (neighbour) if you suffer direct damage (e.g., mould in your home), but this is more delicate.

For the buyer: before buying, check the condition of the common parts adjacent to the unit. If works are necessary, you can act alone after the sale, but it is preferable to negotiate a price reduction or make the sale conditional on their completion.

Example: an untreated leak can lead to restoration costs of €5,000 to €15,000, not counting the loss of value of the property. By acting quickly, you avoid aggravation.

Four tips to avoid this type of dispute

• Have the defects recorded by a bailiff: at the first signs of dampness or cracks, have a report drawn up. This document is irrefutable proof of the existence and extent of the damage. Expect to pay around €150 to €250 for a simple report.
• Inform the managing agent by registered letter with acknowledgement of receipt: even if you can act alone, it is always preferable to put the managing agent on notice to intervene. This creates a written record and may trigger a faster collective action. Keep a copy.
• Gather repair quotes: to quantify your damage, obtain at least two quotes from specialised companies. This will enable you to claim damages corresponding to the actual cost of the works.
• Consult a lawyer lawyer before taking action: the procedure can be complex, especially if the person responsible contests. A lawyer will help you determine whether your damage is indeed personal and choose the most appropriate route (interim proceedings, full hearing, etc.).

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

Further reading: related case law and developments

The 1984 judgment has been confirmed by subsequent decisions. For example, the Court of Cassation held in 2003 (Civ. 3, 10 September 2003, no. 02-12.345) that a co-owner may bring interim proceedings to put an end to an abnormal neighbourhood disturbance caused by a common part, without waiting for authorisation from the general meeting. This case law consolidates the individual right of action.

However, an important limitation: the co-owner cannot act alone to challenge a decision of the general meeting relating to common parts (for example, a refusal to carry out works). In that case, he or she must act within the framework of the condominium, by seeking annulment of the decision. The 1984 judgment concerns only liability actions against a third party or a faulty co-owner.

The current trend of the courts is rather favourable to the individual co-owner, especially since the ALUR law of 2014 which strengthened transparency and the rights of co-owners. However, the issue of the apportionment of costs between co-owners remains delicate: if you obtain damages, must you pay them back to the managing agent if the works concern the whole condominium? The answer depends on the circumstances. In general, the judge awards sums directly to the co-owner for his or her personal damage, and the managing agent handles collective works with the condominium's funds.

What you must absolutely remember

Practical FAQ:

Q: Can I act alone if the party wall is deteriorated, even if the other co-owners do not want to?
R: Yes, since the 1984 judgment, you can act alone if you suffer personal damage (seepage, cracks, etc.). You do not need authorisation from the general meeting.

Q: What must I prove to succeed?
R: You must prove the fault of the person responsible (for example, the neighbour who does not maintain the wall), your damage (bailiff's report, photos, quotes) and the causal link. Article 1240 of the Civil Code is the basis.

Q: What are the time limits for acting?
R: The limitation period is 5 years from the manifestation of the damage (Article 2224 of the Civil Code). Note: if you wait too long, you risk losing your right to act.

Q: Can I claim damages for moral harm?
R: Yes, if the defect causes significant inconvenience (noise, dampness, etc.). Courts generally award modest sums (€500 to €2,000), but this is in addition to the repair costs.

Q: What if the person responsible is insolvent?
R: You can turn to your own home insurance policy, which often covers water damage. Check your contract.

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