Converting Joint Ownership into Co-ownership: A Practical Guide

Inheriting the family building together with one's brothers and sisters often leaves the heirs in an uncomfortable position: each holds a share of the whole, nobody holds anything specific, and the slightest decision requires everyone's agreement. This joint ownership (indivision), which is meant to be temporary, drags on and generates tension. Converting joint ownership into co-ownership (copropriété) is a little-known alternative to partition or sale: it allows each heir to become the owner of an identified unit (an apartment, a commercial premises) while keeping the building in the family. Using the example of a family building, this guide sets out the practical steps of the operation, from the chartered land surveyor (géomètre-expert) to the notary, and explains when it proves more advantageous than a conventional partition.

Joint ownership and co-ownership: two legal regimes that should not be confused

Joint ownership is the situation in which several persons hold the same asset together, without their rights relating to a physically delimited part. It is governed by Articles 815 et seq. of the French Civil Code. Each joint owner (indivisaire) holds an abstract share (a third, a quarter) of the whole building, but none can say "this apartment is mine". Decisions are taken under complex majority rules, and the most significant acts of disposal (selling the building, for example) require unanimity, pursuant to Article 815-3 of the French Civil Code. The rights of each joint owner and the rules for managing jointly owned property are set out in our article on what the Civil Code provides on joint ownership.

Co-ownership follows the opposite logic. Governed by Law No. 65-557 of 10 July 1965 establishing the status of co-ownership of built properties and by its implementing decree No. 67-223 of 17 March 1967, it divides the building into units (lots). Each unit comprises a private part (the apartment itself, of which the owner has full enjoyment) and a share of the common parts (the ground, the load-bearing walls, the roof, the staircase), expressed in ownership shares (tantièmes). Article 1 of the 1965 Law sets out this structure:

This law governs every built property or group of built properties intended wholly or partly for residential use, the ownership of which is divided between several persons into units each comprising a private part and a share of the common parts.

The difference is fundamental for heirs. In joint ownership, one owns a fraction of everything. In co-ownership, one owns something specific, which one may sell, let or mortgage freely, without asking the agreement of the others. Converting joint ownership into co-ownership therefore means moving from collective, abstract ownership to individual, concrete ownership, without having to leave the building.

The case of the family building received in a succession

Take a common situation. Three brothers and sisters inherit, on the death of their parents, an investment building in a town centre, made up of four apartments spread over three floors, plus a commercial premises on the ground floor. The building is in good condition and nobody wishes to sell it, but each has different plans. The eldest would like to occupy the large apartment on the second floor. The middle child would prefer to let his share in order to receive income. The youngest needs cash and is considering selling whatever she receives.

As long as the building remains in joint ownership, none of these plans can be carried out simply. The eldest cannot move into "her own home" since no apartment belongs to her outright. The middle child receives his share of the rent, but remains dependent on collective decisions for management. The youngest can only sell her undivided share, a barely liquid right which hardly interests any outside buyer and is negotiated at a heavy discount.

The division of the family building into co-ownership resolves the problem. Once the building is divided into units and the co-ownership regime is established, each person is allocated one or more units corresponding to his or her share. The eldest receives the second-floor apartment and moves in. The middle child receives one or two units which he lets. The youngest receives a specific unit, a clearly identified apartment that she can sell on the market at a normal price. The family keeps control of the whole, and each becomes master of his or her own property.

This scenario involves two distinct operations that must be kept clearly separate in one's mind. First, the creation of the co-ownership itself, which turns the building into units (this is the subject of this guide). Second, the partition, which allocates the units to the heirs according to their rights. Both can be carried out together in the same notarial deed, but they follow different legal logics.

Step 1: checking the feasibility of the division with a chartered land surveyor

Every creation of a co-ownership begins with a technical phase entrusted to a chartered land surveyor (géomètre-expert), a regulated professional and the only person authorised to prepare enforceable division documents. His or her work conditions everything that follows: a division poorly designed at this stage is paid for later in boundary disputes, errors in ownership shares and litigation between co-owners.

Surveying and measuring the units

The surveyor visits the site to record the exact configuration of the building. He or she identifies what will be private parts (the apartments, the commercial premises, the cellars, any attic space that could be converted) and what will constitute the common parts (the ground, the structural work, the roof, the pipework, the staircase, the courtyard). He or she measures the surfaces, in particular the Carrez law surface area of each unit, the mention of which is mandatory in any subsequent sale pursuant to Law No. 96-1107 of 18 December 1996.

This fieldwork sometimes reveals obstacles. An apartment may have no independent access. Part of the building may encroach on the neighbouring land. The meters (water, electricity, gas) may be shared and need to be individualised. The surveyor flags these points, because a division can only succeed if each unit is physically self-contained and serviced.

Calculating the co-ownership shares

The technical core of the work is the allocation of the ownership shares (tantièmes), that is, the share of the common parts attached to each unit. Article 5 of the 1965 Law requires that this allocation be established according to the nature, surface area and location of the units, regardless of their use. In practical terms, a large, well-exposed apartment on the second floor will be allocated more shares than a small, dark flat on the top floor with no lift.

This allocation is not an accounting detail. It determines both the weight of each co-owner in votes at the general meeting and his or her contribution to the common charges. A calculation error or an arbitrary allocation exposes the co-owners to an action for revision of the shares, available where the share of a unit departs by more than a quarter from that which would result from an allocation compliant with the law. A rigorous calculation from the outset is therefore preferable.

The global technical diagnosis

Where the building being placed under co-ownership is more than ten years old, Article L731-4 of the French Construction and Housing Code requires a global technical diagnosis (diagnostic technique global, DTG) to be carried out beforehand. This document records the apparent condition of the common parts and fittings, assesses the necessary works and estimates their cost over the coming years. For the family building in our example, this diagnosis is both a legal obligation and a valuable tool: it allows the heirs to learn the real condition of the building before fixing the allocation and to anticipate major works (facade renovation, roof repairs).

Step 2: drafting the co-ownership rules and the descriptive statement of division

Once technical feasibility is established, the building must be provided with the two founding documents of every co-ownership: the descriptive statement of division (état descriptif de division) and the co-ownership rules (règlement de copropriété). They are often combined in a single deed.

The descriptive statement of division

The descriptive statement of division is the numbered inventory of the units. It assigns a number to each private part (unit No. 1, unit No. 2), describes its nature (a three-room apartment on the first floor, a cellar in the basement) and states the ownership shares attached to it. It is the document that allows, for each unit, a precise designation in sales deeds and in the property register kept by the land registry (service de la publicité foncière). The consequences of a discrepancy between the descriptive statement of division and the co-ownership rules for the usability of the unit are analysed in our article devoted to that question.

The co-ownership rules

The co-ownership rules drawn up by the notary (or by a chartered land surveyor or a lawyer, but authenticated by the notary for registration) are the charter governing how the building operates. They set out the rights and obligations of each owner. Their drafting requires particular care, because poorly drafted rules produce lasting conflicts between co-owners. They specify in particular:

• the intended use of the building and of each unit (residential, commercial use for the ground floor), which determines the permitted uses
• the detailed definition of the common parts and the private parts, a classic source of disputes when it is imprecise (who owns the balcony, the window, the flue?)
• the rules of enjoyment (prohibition of noisy activities, conditions for keeping animals, appearance of the facades)
• the allocation of charges, distinguishing between general charges for upkeep and administration, apportioned according to the ownership shares, and special charges linked to collective services and fittings, apportioned according to the objective utility each unit derives from them, in accordance with Article 10 of the 1965 Law.

For the family building, the rules will have to settle practical questions: may the ground-floor commercial premises house a restaurant, with the nuisance that this implies for the dwellings? Should the upkeep of the lift, which the commercial premises do not use, fall on its owner? These decisions, set out clearly from the outset, avoid years of litigation. The mandatory content of the rules and the fate of clauses deemed unwritten are examined in our article on the clauses of the co-ownership rules.

The question of the small co-ownership

Since the reforms resulting from Ordinance No. 2019-1101 of 30 October 2019, made pursuant to the ELAN Law No. 2018-1021 of 23 November 2018, the law provides for a lighter regime for small co-ownerships. Co-ownerships comprising no more than five units for residential, office or commercial use, or whose average forecast budget is below a regulatory threshold, benefit from simplified operating rules, in particular for decision-making. A family building divided into a few units often falls within this regime, which lightens day-to-day management: less formality, not necessarily a professional property manager (syndic), and more flexible decision-making between members of the same family.

Step 3: the role of the notary and registration at the land registry

As the building is real property, the creation of the co-ownership takes effect against third parties only after it has been authenticated by a notary and registered at the land registry (service de la publicité foncière). This step is not a mere formality: it gives a certain date and enforceability to the new organisation of the building.

Authentication and registration of the deed

The notary receives the descriptive statement of division and the co-ownership rules in the form of an authentic deed. He or she checks the consistency of the documents, the concordance of the ownership shares, compliance with town planning rules and the mortgage position of the building. The notary then registers the deed in the property register. From that registration, the building exists legally as a co-ownership: each unit has its own identified and transferable existence.

Coordination with the partition of the estate

It is also the notary who, in the context of the succession, will carry out the partition of the units between the heirs. Once the building is divided, the partition deed allocates to each heir the unit or units corresponding to his or her rights. If the units are not of equal value, the person receiving more pays the others an equalisation payment (soulte), that is, a financial compensation. In our example, if the eldest's apartment is worth more than the theoretical share due to her, she compensates her brothers and sisters for the difference. The partition ends the joint ownership: each becomes sole owner of his or her unit.

The cost of the operation

The operation requires an investment that should not be overlooked: the surveyor's fees, the cost of the global technical diagnosis, the notary's remuneration (whose fees are regulated), land registration duties and, in the event of a partition, partition duty assessed on the net value of the property divided. These costs vary according to the size of the building and the complexity of the division. They must be weighed against the asset-related advantages of the operation, discussed below. A preliminary consultation makes it possible to prepare an estimate suited to each situation.

Co-ownership or partition: when division is more advantageous

Faced with joint ownership of real property, heirs have several ways out. Article 815 of the French Civil Code sets out the cardinal principle:

No one may be compelled to remain in joint ownership, and partition may always be sought, unless it has been stayed by judgment or agreement.

The most conventional exit is outright partition, possibly followed by a sale. But creating a co-ownership offers decisive advantages in several configurations.

When no heir wishes to sell the building

If the heirs wish to keep the family property, the partition of an undivided building runs into a practical difficulty: a building in a single block cannot be cut into three. The court, seised of a request for partition, may then order a sale by auction (licitation), which frequently results in the loss of the property and a price below its real value. Creating a co-ownership avoids this pitfall: by creating separate units, it makes the partition physically possible and allows each person to leave with a tangible asset rather than a sum of money from a forced sale.

When one heir wishes to sell and the others do not

This is the most frequent and the most conflictual situation. A joint owner in a hurry to recover cash may, at any time, seek a judicial partition and threaten the whole with a sale by auction. Converting joint ownership into co-ownership defuses this risk: the heir who wishes to sell receives a specific unit which he or she sells freely on the market, while the others keep theirs without being exposed to an imposed sale of the whole. Each regains his or her freedom without sacrificing that of the others.

When the building generates rental income

For an investment building, co-ownership offers a flexibility of management that joint ownership does not. In joint ownership, income and charges are shared in proportion to the shares, and collective management is a source of deadlock. In co-ownership, each owner lets his or her unit as he or she sees fit, collects the rent, undertakes his or her own works and alone declares the property income. Taxation becomes individual, which allows each person to optimise his or her situation according to his or her tax bracket.

When the value of the property is at stake

A building divided into co-ownership units is generally worth more, for the same floor area, than the same building sold as a whole. The market for individual apartments is wider and more liquid than that for entire buildings, which is reserved for investors. Creating a co-ownership is therefore also an operation to enhance the value of the estate, particularly relevant where the heirs envisage staggered sales in due course.

Conversely, creating a co-ownership is of little interest where all the heirs agree to sell the building as a whole quickly, or where the layout of the premises makes the division technically impossible or disproportionate to the costs. The decision is made case by case, in light of each person's plans and the condition of the property.

Conclusion

Converting joint ownership into co-ownership is neither a marginal arrangement nor a mere administrative formality: it is a genuine reorganisation of ownership that gives each heir his or her freedom without sacrificing the family estate. Where joint ownership freezes and divides, co-ownership distinguishes and frees. The operation nevertheless requires flawless technical and legal rigour, from the surveyor's measurements to the calculation of the ownership shares, from the drafting of the co-ownership rules to notarial authentication and registration at the land registry.

The position is clear: where the heirs do not all agree to sell as a whole and the building lends itself physically to division, creating a co-ownership is almost always preferable to a sale by auction that is forced upon them. It preserves the property, enhances the value of the estate and prevents future conflicts. Before committing, have the feasibility of the division checked by a chartered land surveyor and have the drafting of the co-ownership rules secured by a professional: it is the quality of these founding documents that will determine, for decades, the smooth running of the co-ownership you create.

Frequently asked questions

Can joint ownership be converted into co-ownership without the agreement of all the joint owners? Creating a co-ownership is an act of disposal which, in principle, requires the unanimity of the joint owners pursuant to Article 815-3 of the French Civil Code. Failing an amicable agreement, a joint owner may apply to the court to seek partition on the basis of Article 815. The court may then, if division is possible, order the creation of units rather than a sale by auction. A prior agreement between heirs always remains the quickest and least costly route.

How long does it take to divide a family building into co-ownership? The duration depends on the size of the building and the complexity of the division. One must allow for the time taken by the surveyor's survey and calculations, the carrying out of the global technical diagnosis for a building more than ten years old, the drafting of the co-ownership rules, and then authentication and registration by the notary. In practice, the operation takes several months. A disagreement between heirs or technical obstacles can significantly lengthen this period.

What is the difference between partition and the creation of a co-ownership? They are two distinct but complementary operations. The creation of a co-ownership divides the building into identified units carrying ownership shares, and transforms the structure of the property. The partition then allocates these units to the heirs according to their rights and ends the joint ownership. A building can be divided into co-ownership and then partitioned, both often being carried out in the same notarial deed.

Is the global technical diagnosis mandatory for every creation of a co-ownership? Yes, where the building is more than ten years old at the time it is placed under co-ownership, Article L731-4 of the French Construction and Housing Code requires a global technical diagnosis to be carried out beforehand. This document describes the condition of the common parts and fittings and assesses the works to be anticipated. It protects the future co-owners by giving them a clear view of the real condition of the building.

Who calculates the ownership shares and how are they determined? The ownership shares are established by the chartered land surveyor at the time of the division. In accordance with Article 5 of the Law of 10 July 1965, they are calculated according to the nature, surface area and location of each unit, regardless of the use made of it. They determine the weight of each co-owner in votes and his or her contribution to the general charges. An erroneous allocation may give rise to an action for revision where the discrepancy exceeds a quarter of the value that would result from a compliant allocation.

Must a small family co-ownership necessarily have a professional property manager (syndic)? No. The regime for small co-ownerships resulting from the Ordinance of 30 October 2019 lightens the operating obligations for buildings of no more than five units or whose forecast budget remains below a regulatory threshold. In a family setting, the co-owners may appoint one of themselves as a non-professional property manager, which reduces management costs. A professional property manager nevertheless remains advisable where the co-ownership is larger or relations between co-owners are strained.

Does creating a co-ownership increase the value of the building? As a general rule, yes. A building divided into co-ownership units sells, for an equivalent floor area, at a higher price than the same building sold as a whole, because the market for individual apartments is wider and more liquid. Division is therefore also a strategy for enhancing the value of the estate, particularly suited where the owners envisage staggered sales over time.