Reference Decision: cc • No. 16-26.072 • 2018-01-18 • View the decision →
Imagine you own a large flat in a residence in Parentis-en-Born, in the heart of the Landes region. You wish to divide it to create two separate dwellings and sell them individually. A simple idea, right? But here's the catch: this seemingly straightforward operation can trigger a genuine legal imbroglio. What happens if the new purchasers want to create their own association, separate from that of the building? The question is not theoretical: it arises daily in co-ownerships from Mont-de-Marsan to Dax.
In reality, this situation raises a fundamental problem: can dividing a unit give rise to a new co-owners' association (the body that manages the co-ownership)? The answer, you guessed it, is no. But why this prohibition, and what are its practical consequences? This is what the Court of Cassation (the highest French judicial court) clarified in a key 2018 decision.
This decision, often unknown to owners, has concrete implications for building management, service charges, and even property values. It reminds us of an essential rule: co-ownership is a coherent legal structure that cannot be fragmented at will. But what exactly does this change for you, as an owner, tenant, or real estate professional? Let's delve into the details.
The Facts: A Story That Happens Every Day
The case begins in a typical co-ownership, a building divided into several units (flats, garages, etc.). Mr. Durand, owner of a large commercial premises on the ground floor, decides to divide it into two separate shops. He sells the first premises to Mrs. Martin and keeps the second for himself. So far, nothing extraordinary: dividing units is a common practice, particularly in town centres like Mont-de-Marsan where commercial demand is strong.
But things become complicated when Mrs. Martin and Mr. Durand, now co-owners of these two new units, decide to create their own association. They believe their interests are specific (management of commercial façades, opening hours, etc.) and deserve an organisation separate from the main association of the building. The main association firmly opposes this: according to them, this creation would be illegal and would disrupt the overall management of the co-ownership.
The conflict escalates. Mrs. Martin and Mr. Durand take the matter to court to assert their right to an autonomous association. They argue that their situation is particular, almost a "co-ownership within the co-ownership." The court of first instance rules in their favour, considering that the division of the initial unit justifies a separate organisation. The main association appeals, but the court of appeal confirms the first judgment. Twist: the main association appeals to the Court of Cassation, supported by several co-owner associations fearing a dangerous precedent.
Finally, the case reaches the Court of Cassation. The stakes are clear: if the creation of a new association is validated, it could pave the way for fragmentation of co-ownerships, with multiple associations within the same building. A prospect that worries professionals, as it would complicate management, works, and the apportionment of service charges. The story of Mr. Durand and Mrs. Martin, ordinary at first, thus becomes a textbook case for all co-ownership law.
The Court's Reasoning — Analysed
The Court of Cassation, in its judgment of 18 January 2018, quashes the decisions of the lower courts. Its reasoning rests on two essential legal pillars. First, Article 8 of the Law of 10 July 1965 (the founding text of co-ownership), which defines co-ownership as the organisation of a built property divided into units. In short, co-ownership is unique per building: one cannot have several associations for the same structure.
Secondly, the court relies on consistent case law (the body of previous court decisions) which prohibits the creation of "secondary co-ownerships" within a main co-ownership. In other words, even if a unit is divided, it remains subject to the single association of the building. The judges explain that dividing a unit does not modify the overall legal structure: it simply creates new units, but not a new co-ownership.
The court analyses the arguments of both parties with precision. Mrs. Martin and Mr. Durand argued that their situation justified an exception, as their units formed an autonomous entity (a "vertical co-ownership" parallel to the "horizontal co-ownership" of the building). The court rejects this argument: it recalls that the coexistence of several vertical co-ownerships within the same building is legally impossible. Division gives rise to distinct units, but not to an autonomous co-ownership.
What few people know is that this decision confirms older case law, but clarifies it in a modern context where unit divisions are frequent. It does not innovate radically, but it closes the door to any attempt at circumvention. However, beware: this does not mean division is prohibited; it is possible, but it must respect the unique framework of the existing association. In practice, if you divide a unit, you must inform the association and update the co-ownership regulations (the document setting out the rules of living and management), but you cannot create your own organisation.
What This Changes for You — Concretely
For a landlord (who lets their property), this decision has direct implications. If you divide a unit to create two rental dwellings, for example in a building in Mont-de-Marsan, you must know that the two new units remain subject to the same association. Concretely, this means that service charges (maintenance, repairs) will be apportioned according to the thousandths (the co-ownership shares) set in the regulations. If you hoped to create a mini-association to specifically manage these two dwellings, it is impossible. undefined, I have encountered cases where owners had undertaken division works without anticipating this rule, generating costly conflicts with the main association.
For a tenant, the impact is more indirect but real. If your landlord divides the unit, your lease (the tenancy agreement) could be affected if works modify the configuration of the premises. You must verify that the division respects the co-ownership regulations and does not create disturbances (noise, access, etc.). How to react? Demand clear information from the landlord and, in case of doubt, consult the association.
For a purchaser, this decision is crucial. Before buying a unit resulting from a division, verify that the situation is regular with the association. Otherwise, you risk surprises: for example, misapportioned service charges or disputes with other co-owners. A realistic numerical example: in a Landes co-ownership, a purchaser discovered after the purchase that the division had not been declared, leading to regularisation with costs of €5,000. If you are in this situation, you must request a certificate from the association confirming that the division is compliant.
For an ordinary co-owner, this decision reinforces the stability of the co-ownership. It avoids the multiplication of associations, which would complicate decisions (such as votes in general meetings) and daily management. In short, it protects the collective interest against individual initiatives. But it also imposes vigilance: any division must be approved in a general meeting, with a reflection period and a cost (budget €1,000 to €3,000 for legal and technical formalities).
Four Tips to Avoid This Type of Dispute
- Consult the co-ownership regulations before any division: Verify if division is authorised and what conditions apply (for example, the agreement of the general meeting). In residences in Parentis-en-Born, some regulations prohibit divisions outright to preserve the balance of the premises.
- Inform the association as soon as the project begins: Do not start works without speaking to the association. Early communication allows anticipation of regulation modifications and avoids conflicts. undefined, I have seen cases where a simple discussion beforehand allowed amicable resolution.
- Have a descriptive statement of division prepared by a surveyor-expert: This technical document specifies the new units and their thousandths. It is essential for updating co-ownership documents and avoiding service charge errors. Budget approximately €1,500 for this service in the Landes region.
- Do not attempt to create a parallel association: Even if your units seem autonomous, respect the single association. Otherwise, you risk legal action from the main association, with legal fees and potential damages.
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Deep Dive: Related Case Law and Developments
This decision fits into a consistent line of case law. For example, a Court of Cassation judgment of 15 December 2010 (No. 09-67.098) had already recalled that dividing a unit does not create a new co-ownership. However, the 2018 decision goes further by specifying that even the idea of an autonomous "vertical co-ownership" is inadmissible. It thus closes a loophole that some owners were attempting to exploit.
There are no major divergent decisions on this point, as the courts are unanimous: co-ownership is an indivisible whole. The trend is clearly towards protecting the unity of the association, facing pressures from property individualism. What does this mean for the future? Real estate professionals will need to be even more vigilant about divisions, and owners will have to accept that collective management takes precedence over personal desires. In a context where ageing co-ownerships in the Landes require costly works, this legal stability is good news for the longevity of buildings.
Frequently Asked Questions
Q: I want to divide my flat into two studios. Is this possible?
A: Yes, but you must obtain the agreement of the general meeting of co-owners and update the co-ownership regulations. You cannot create a new association to manage these studios.
Q: What are the risks if one creates a parallel association?
A: The main association can take legal action to have this creation annulled. You will have to pay procedural costs and potentially damages for abnormal neighbourhood disturbance.
Q: How are service charges apportioned after a division?
A: Service charges are apportioned according to the new thousandths set in the descriptive statement of division. For example, if your initial unit was worth 100 thousandths and you divide it into two units of 50 each, each new unit will pay proportionally.
Q: Does this decision apply to horizontal co-ownerships (housing estates)?
A: No, it specifically concerns vertical co-ownerships (buildings). For housing estates, the rules are different, with secondary associations often authorised.
Q: What to do if the association refuses the division?
A: You can attempt to negotiate or, as a last resort, take the matter to court to assert your right, but it is a lengthy and costly procedure. Better to anticipate by consulting a specialised solicitor.
Do you find yourself in a similar situation? A first 30-minute consultation with Maître Zakine (€45) can save you months of procedure — and often much more. Book an appointment →

