Leading Decision: French Cour de cassation • No. 80-15.132 • 25 January 1983 • View decision →
You own a house in Carpentras, held in indivision with your brother following an inheritance. A neighbour, without permission, drives beams into your party wall to extend his barn. You want to react quickly, but your brother is unreachable. What can you do? Does the law allow you to act alone?
This is precisely the question the French Cour de cassation had to decide in 1983. Article 815-2 of the French Civil Code allows any co-owner to take alone the "measures necessary for the preservation of the jointly owned property." But this concept is more restrictive than it appears.
This decision sets a clear limit: a legal action that challenges a property right (such as the removal of beams from a non-party wall) is not a conservatory act, unless there is imminent peril. Deciphering the issue.
The Facts: A Story as Common as Any
Mr. Louis is a co-owner of a building in Avignon, with a wall separating his property from that of his neighbour, Mr. Z. This wall is partly private (belonging exclusively to the indivision) and partly party (shared between the two properties). Without agreement, Mr. Z drives beams into the private wall to support a construction and raises the party wall to support his roof.
Mr. Louis, alone, without the consent of the other co-owners, sues Mr. Z in court to obtain the removal of the beams and the demolition of the raising. He invokes Article 815-2 of the French Civil Code, arguing that this is a conservatory measure necessary to protect the jointly owned property.
The Court of Appeal of Nîmes declares his action inadmissible: a co-owner cannot act alone for this type of claim. Mr. Louis appeals to the Cour de cassation. The Cour de cassation dismisses his appeal and confirms the inadmissibility. It holds that the action did not aim to remove the property from imminent peril — it was not shown that Mr. Z risked acquiring a right of support by expropriation-indemnisation-terrain" class="internal-link" title="Servitudes d'urbanisme et expropriation">thirty-year prescription, nor that the works compromised the building's stability. Consequently, this action exceeds the limits of conservatory acts.
The Court's Reasoning — Analysed
The Cour de cassation relies on Article 815-2 of the French Civil Code, which provides: "The measures necessary for the preservation of the jointly owned property may be taken by any co-owner." But it clarifies the meaning of this provision: these measures are physical or legal acts aimed at removing the jointly owned property from imminent peril without seriously compromising the rights of the co-owners.
In other words, two cumulative conditions must be met:
- An imminent peril (immediate danger to the property).
- An act that does not affect the rights of the other co-owners.
In this case, Mr. Louis's claim — removal of beams and demolition of the raising — did not meet these criteria. On the one hand, no imminent peril was established: the neighbour's works did not threaten the building's stability, and there was no risk of acquisitive prescription (usucapion) of the right of support. On the other hand, the legal action itself was a challenge to the neighbour's property right, which goes beyond mere preservation.
The Court therefore rejects Mr. Louis's argument that his action was conservatory. It confirms the position of the Court of Appeal: a single co-owner cannot bring an action that, by its nature, goes to the substance of the law (property, easement) without the consent of the others. This is not a reversal but a confirmation of prior case law.
What few people know is that this decision clearly distinguishes conservatory acts (e.g., urgently repairing a water leak) from administrative or dispositive acts (e.g., selling the property or bringing a possessory action). A single co-owner may do the former, but not the latter.
However, beware: if the peril is real and imminent (e.g., a wall threatening to collapse), a legal action to stop the danger could be considered conservatory. But in this case, simply driving beams without urgency is not enough.
What This Means for You — Practically
Co-owners: If you are in indivision and a neighbour encroaches on the property, do not rush to court alone. You must first obtain the agreement of all co-owners, or failing that, obtain permission from a judge. Otherwise, your action will be declared inadmissible, like Mr. Louis. Concrete example: in Cavaillon, a co-owner tried alone to have a fence built by a neighbour on the jointly owned plot demolished. The court dismissed her claim for lack of agreement from the other heirs.
Tenants: You are not directly concerned by indivision, but if your landlord is in indivision, note that a single co-owner cannot give you notice or modify the lease without the consent of the others (except in an emergency).
Buyers: Before buying a property held in indivision, check that all co-owners consent to the sale. A single co-owner cannot sell alone, except in very limited cases (Art. 815-5 of the French Civil Code).
Co-owners in condominiums: Indivision is different from condominium ownership, but the principle is similar: important acts require majority consent. If a condominium owner acts alone for works affecting common parts, the decision can be challenged.
undefined, I have come across cases where a co-owner had emergency works carried out (roof repair after a storm) without consulting the others. That was conservatory and therefore valid. But when it comes to a legal action against a third party, the threshold is higher.
Four Tips to Avoid This Type of Dispute
- Obtain written consent from all co-owners before any legal action. Even if you consider the action urgent, a simple email or recorded delivery letter may suffice. If there is a refusal, apply to the judge for authorisation.
- In a genuine emergency (risk of collapse, fire, etc.), document the peril with photos, bailiff's reports, or expert reports. This will allow you to justify a conservatory action.
- Do not confuse a conservatory act with an administrative act. A conservatory act aims to avoid immediate damage (repairing a leak). An administrative act manages the property (leasing). A dispositive act affects the assets (sale). Only the first can be done alone.
- Consult a lawyer before acting alone. A 30-minute legal consultation can save you time and money in an inadmissible procedure.
Further Reading: Related Case Law and Developments
This 1983 decision is part of a consistent line: the Cour de cassation has always interpreted Article 815-2 strictly. For example, in a judgment of 13 December 1994 (No. 92-21.567), it held that a co-owner could not alone bring a boundary action (property delimitation), because it affects property rights.
Conversely, in a decision of 8 February 2005 (No. 02-18.182), the Court held that a co-owner could alone have works carried out to bring a building into compliance with safety standards, because there was imminent peril (fire risk).
The trend is therefore clear: judges are strict on the notion of "imminent peril." If you want to act alone, you must demonstrate a concrete and immediate danger. In the future, case law may evolve with the development of forced indivision (complex inheritances), but for now, the rule remains the same.
Checklist Before Acting
- Am I alone or in indivision? Check the title deed and inheritance document.
- Is the act I want to take conservatory? Ask yourself: is there an imminent peril? Does the act affect the rights of others?
- Do I have the consent of the other co-owners? If yes, formalise it in writing. If no, can I obtain a judge's authorisation?
- What is the urgency? If the property is in danger (e.g., gas leak), act quickly and document it. Otherwise, take time to consult.
- Have I consulted a lawyer? Before any legal action, professional advice is essential.
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📌 Does this apply to your situation? Maître Cécile Zakine, French real estate lawyer, practises throughout France.
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