Compulsory Chartered Surveyor: Is Your Co-Ownership Plan Valid?

Imagine yourself in Capbreton, facing the ocean, in your second home. You bought an apartment a few years ago with a terrace clearly delineated on the plan. But now a neighbour is contesting the boundaries, arguing that the plan annexed to the co-ownership deed is unreliable. Who is right?

This situation is one I encounter regularly in my practice, whether in Mont-de-Marsan, Parentis-en-Born, or elsewhere in the Landes. Owners often find themselves helpless in the face of imprecise plans or those prepared by non-professionals. The question is simple but crucial: must a co-ownership plan that delimits your property rights necessarily be prepared by a chartered surveyor?

The Court of Cassation has just clearly answered this question in a decision of 29 June 2022. This answer goes far beyond a mere technical point—it touches the heart of the legal security of your real estate assets. But what exactly does this change for you, as an owner, tenant, or real estate professional?

The facts: a story as common as any

Mr Dupont, owner of a unit in a co-ownership in Parentis-en-Born, discovers one day that the plan annexed to his title deed does not correspond to the reality of the land. This plan, a simple black-and-white document, had been prepared by the developer's architect during the construction of the residence, without the involvement of a chartered surveyor.

The problem arises when Mr Martin, a neighbouring co-owner, builds a fence that encroaches on what Mr Dupont considers his property. Mr Dupont then consults the co-ownership plan, but it is so imprecise that it cannot resolve the dispute. Worse still: he discovers that another plan, certified as 'sincere and true' by the initial seller, presents a parcel division (i.e., a division of the land into plots) incompatible with the first document.

Faced with this confusion, Mr Dupont takes legal action. He contests the validity of the co-ownership plan, arguing that such an important document, which delimits each person's land rights, can only be prepared by a chartered surveyor. The court of appeal, however, rejects his claim, considering that 'it matters little that it was not prepared by a chartered surveyor'.

Mr Dupont does not give up and lodges an appeal to the Court of Cassation. This is where the case takes a decisive turn for all French owners. The Court of Cassation will examine whether this position of the court of appeal complies with the law governing the profession of chartered surveyor.

The court's reasoning—analysed

The Court of Cassation, in its judgment of 29 June 2022, quashes the decision of the court of appeal. Its reasoning is based on a strict interpretation of Law No. 46-942 of 7 May 1946 establishing the Order of Chartered Surveyors, as amended by Law No. 87-998 of 15 December 1987.

The judges recall that this law aims to guarantee the free exercise of the profession of chartered surveyor. More specifically, they emphasise that only chartered surveyors registered with their order can carry out 'the studies and topographical works that fix the boundaries of land assets'. In other words, as soon as it comes to determining where your property begins and ends, only a chartered surveyor is authorised to intervene.

The Court elaborates: chartered surveyors have the mission to 'survey and draw up, at all scales and in whatever form, the topographical plans and documents concerning the definition of rights attached to land ownership'. This wording explicitly includes 'the plans for division, partition, sale, and exchange of land assets, the plans for boundary marking or delimitation of land ownership'.

However, in Mr Dupont's case, the plan annexed to the co-ownership deeds did delimit the land rights of the co-owners. The court of appeal therefore violated the law by considering that the qualification of the professional was not important. In short, the Court of Cassation establishes that any plan used to define property rights in a co-ownership must be prepared by a chartered surveyor—full stop.

This reasoning confirms a consistent line of case law: the delimitation of land assets is a reserved activity, on the same footing as the authentication of deeds by a notary. It is a matter of legal security for all.

What this changes for you—concretely

If you are the owner of a unit in co-ownership, this decision directly concerns you. From now on, you can contest the validity of a co-ownership plan if it has not been prepared by a chartered surveyor. Concretely, this means that the boundaries of your property as indicated on this plan could be called into question.

Take an example in Capbreton: you buy an apartment with a 50 m² terrace for €300,000. If the plan is not prepared by a chartered surveyor, and a dispute arises, you could lose part of this area. The value of your property could then drop by 10 to 20%, i.e., €30,000 to €60,000 less on resale.

If you are a tenant, this decision indirectly protects you. A precise plan avoids conflicts between neighbours that could degrade your quality of life. If you are a purchaser, systematically check the origin of the plan before signing. Ask to see the chartered surveyor's certificate—it is your strict right.

For co-owners, this decision offers a valuable weapon. You can now demand the regularisation of defective plans. Be careful, however: this regularisation by a chartered surveyor costs between €1,500 and €3,000 for an average co-ownership, to be shared among all co-owners.

If you are in this situation, you must act within 5 years from the discovery of the defect. After this period, you could be time-barred (i.e., lose your right to take action). undefined, I have encountered cases where owners waited too long and lost considerable sums.

Four tips to avoid this type of dispute

• Systematically check the origin of the plan before any property purchase. Demand the certificate from the chartered surveyor who prepared it, with their registration number with the order.
• Have a boundary marking (precise delimitation by physical markers) carried out by a chartered surveyor if you have the slightest doubt about the boundaries of your property, especially in areas like Parentis-en-Born where land is often vast.
• Consult the co-ownership regulations and its annexes with a legal professional. A non-compliant plan can lead to partial nullity of the deed.
• Act quickly in case of dispute. The longer you wait, the more evidence disappears and the more complex and costly the procedure becomes.

In-depth analysis: related case law and developments

This decision fits into a consistent line of case law from the Court of Cassation. Already in 2015 (judgment No. 14-10.305), the Court had recalled that 'the operations of boundary marking and delimitation of land properties fall within the monopoly of chartered surveyors'. The 2022 decision reinforces this position by explicitly extending it to co-ownership plans.

What few people know is that some courts of appeal tended to be more flexible, accepting plans prepared by architects or developers. The Court of Cassation puts an end to this divergent practice. From now on, the requirement for a chartered surveyor is absolute as soon as the plan serves to define land rights.

This jurisprudential evolution (i.e., the evolution in how judges interpret the law) corresponds to a broader trend: the increasing judicialisation of real estate disputes. Courts are becoming stricter on compliance with formalities, in the name of transaction security.

Frequently asked questions

My co-ownership plan dates from the 1980s and was not prepared by a chartered surveyor. Is it void?
Not necessarily void, but it is contestable. You can request its regularisation or replacement by a chartered surveyor-prepared plan.

How much does a chartered surveyor-prepared plan cost for a co-ownership?
Between €1,500 and €5,000 depending on the complexity and size of the co-ownership, to be shared among all co-owners.

Can I sell my property with a non-chartered surveyor plan?
Yes, but you must inform the purchaser of the defect. Otherwise, you incur liability and risk an action for latent defects.

What to do if my neighbour contests boundaries based on a non-compliant plan?
Immediately consult a specialised lawyer. Mediation can often avoid a long and costly lawsuit.

Does this rule also apply to individual houses?
Yes, as soon as a plan delimits land rights, regardless of the nature of the property.

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