Ten-year, two-year or completion guarantee: which cover applies to which defect?

A private individual building a house, a property manager (syndic) running a new block or a company taking delivery of commercial premises all ask the same question as soon as a defect appears: who can be pursued, on what legal basis and, above all, within what time limit? A crack in a façade, a boiler that breaks down or double glazing that lets water through do not fall under the same guarantee or the same period of protection. Confusing the completion guarantee (garantie de parfait achèvement), the two-year guarantee (garantie biennale) and the ten-year guarantee (garantie décennale) leads to acting out of time or on the wrong basis, and therefore to losing any remedy. This guide sets out the three statutory construction guarantees, provides a comparative table by type of damage (waterproofing, boiler, joinery) and explains in practical terms who covers what and for how long.

Three guarantees, one starting point: acceptance of the works

The statutory construction guarantees are based on Articles 1792 et seq. of the French Civil Code. They apply only to new structures or to works treated as construction, and all of them run from the same event: acceptance of the works (réception).

Acceptance is the act by which the client (maître d'ouvrage, the person who commissioned the works) declares that it accepts the structure, with or without reservations. It takes the form of a signed, dated report drawn up with both parties present. This document is essential: it starts the countdown for the three guarantees. Without acceptance there is no starting point, but also no cover under these statutory guarantees. The forms of acceptance and its effects on the allocation of risk are described in our article on acceptance of works.

At the time of acceptance, the client records its reservations, that is, the apparent defects it notes (a cracked tile, a door that closes badly, scratched paint). Apparent defects that are not the subject of a reservation are in principle cleared: they can no longer be claimed afterwards, unless they worsen to the point of falling within the ten-year guarantee. Latent defects remain covered according to their nature.

From that single date, three clocks start in parallel: one year for completion, two years for proper functioning, ten years for the ten-year guarantee. The practical difficulty is that the same defect may, depending on its seriousness, move from one guarantee to another.

The completion guarantee: one year for everything that is notified

The completion guarantee is provided for by Article 1792-6 of the French Civil Code. It lasts one year from acceptance and falls exclusively on the contractor who carried out the works, never on its insurer.

The contractor is bound, for a period of one year from acceptance, to make good all defects notified by the client, either by means of reservations recorded in the acceptance report or by written notice for those revealed after acceptance. (Article 1792-6 of the French Civil Code)

Its scope is the widest of all the guarantees: it covers absolutely all defects, whatever their seriousness, whether a minor cosmetic flaw or a more serious problem. It does not matter whether or not the defect compromises the soundness of the structure. The only condition is that it has been notified, either in the reservations in the acceptance report or by written notice sent to the contractor within the year.

In practice, this guarantee covers two categories: the reservations made on the day of acceptance and the defects revealed during the first year. A private individual who discovers, three months after moving in, that an electrical socket does not work or that a window sticks sends a registered letter to the contractor, which must then intervene. The time allowed for carrying out the repairs is fixed by agreement; failing that, it is ordered by the court. On the means available to the client to obtain the remedial work during that year, see our analysis of the completion guarantee.

The point to watch: this guarantee excludes defects resulting from normal wear and tear or from abnormal use of the structure. Above all, it expires definitively after one year. After that period, one must move to the two-year or ten-year guarantee depending on the nature of the defect.

The two-year guarantee of proper functioning: two years for separable equipment

The two-year guarantee, also called the guarantee of proper functioning (garantie de bon fonctionnement), is found in Article 1792-3 of the French Civil Code. It lasts at least two years from acceptance and applies to a specific category: items of equipment that are separable from the structure (éléments d'équipement dissociables).

The other items of equipment of the structure are subject to a guarantee of proper functioning for a minimum period of two years from its acceptance. (Article 1792-3 of the French Civil Code)

An item of equipment is said to be separable when it can be removed, replaced or taken out without damaging the structure of the building. The practical test applied by the case law: can the equipment be removed without damaging the structural work (gros œuvre)? If so, the item is separable and, as a rule, falls under the two-year guarantee.

Typically within this scope are: radiators, hot water cylinders, taps and fittings, shutters and blinds, interior doors, entry phones, portable air conditioning, ventilation units (VMC) and certain joinery elements. Understanding how the ten-year and two-year guarantees fit together requires a clear grasp of this distinction between what concerns the structure and its waterproofing (ten-year) and what is a replaceable comfort item of equipment (two-year).

The two-year guarantee applies when the equipment ceases to work properly, without making the dwelling unfit for its purpose or threatening its soundness. An electric roller shutter whose motor fails after eighteen months, a radiator that no longer heats while the rest of the installation works, a noisy ventilation unit: these are all situations in which the client claims repair or replacement on the basis of Article 1792-3.

As with the ten-year guarantee, this guarantee may be covered by insurance, but relying on it does not require showing any impairment of the soundness of the structure. It is enough to establish that the equipment is malfunctioning.

The ten-year guarantee: ten years for serious defects

The ten-year guarantee is the best known and the most protective. It arises under Articles 1792 and 1792-2 of the French Civil Code and covers the most serious damage for ten years from acceptance.

Any builder of a structure is liable as of right to the owner or purchaser of the structure for damage, even resulting from a defect in the ground, which compromises the soundness of the structure or which, by affecting it in one of its constituent elements or one of its items of equipment, renders it unfit for its purpose. (Article 1792 of the French Civil Code)

Two alternative criteria trigger the ten-year guarantee, and it is enough for one of them to be met. First criterion: the damage compromises the soundness of the structure, for example through cracks running right through the structure, subsidence of foundations or partial collapse. Second criterion: the damage renders the structure unfit for its purpose, that is, prevents it from being used normally, without necessarily affecting its soundness.

It is this second criterion that explains why apparently minor defects can fall within the ten-year guarantee. A roof that lets water through does not collapse, but it makes the house uninhabitable: it therefore falls within the ten-year guarantee. The link between defective waterproofing and the ten-year guarantee is central here, and we return to it below.

The ten-year guarantee has two major advantages. First, it is a liability as of right: the client does not have to prove fault on the part of the builder, only the damage and its ten-year character. Second, it is backed by a double compulsory insurance: the builder's ten-year liability insurance (Article L. 241-1 of the French Insurance Code) and the structural damage insurance (assurance dommages-ouvrage) taken out by the client (Article L. 242-1 of the same Code). The latter makes it possible to obtain advance financing of the repairs without waiting for a court to identify the party responsible.

Article 1792-2 extends the ten-year guarantee to certain items of equipment where they form an integral part of the structure, that is, where they cannot be separated from the structural work (for example a heating system built into the slabs, or a concealed pipe). Their removal or replacement cannot be carried out without damaging the structure: they then follow the ten-year regime.

Comparative table by type of defect: who covers what and for how long

The following table matches the most frequent defects with the applicable guarantee and its duration. It should be read as a first-sort grid: the final classification always depends on the actual seriousness of the defect and its effect on the use of the building.

The logic of this table is easy to remember. During the first year, everything that is notified falls under the completion guarantee. Beyond that, the question becomes: does the defect concern separable equipment that is working badly (two-year), or does it compromise the soundness or use of the building (ten-year)?

Waterproofing defects, the natural territory of the ten-year guarantee

A waterproofing defect and the ten-year guarantee form an almost automatic pairing. Where water gets in, through the roof, an accessible terrace, a façade or badly fitted joinery, the defect is generally analysed as rendering the structure unfit for its purpose. A dwelling in which water runs down the walls, where damp damages the plaster and encourages mould, can no longer be lived in normally.

The courts traditionally apply the ten-year classification to roof leaks, rising damp linked to a foundation defect, terrace leaks and façade waterproofing defects, including where the defect appears only several years after acceptance, provided it remains within the ten-year period. It does not matter whether the ingress is slow or localised: what counts is its effect on habitability.

A point often overlooked: even a waterproofing defect that has not yet manifested itself may be covered if the defect is certain in its development. The case law accepts that the ten-year character is assessed not only in light of present defects but also of those that will certainly occur within the guarantee period.

The boiler, between the two-year and the ten-year guarantee

The ten-year guarantee for a boiler is a tricky question, because the answer depends entirely on the consequences of the breakdown. A boiler is in principle a separable item of equipment: it can be replaced without touching the structure of the building. On that basis, a simple malfunction, a repairable breakdown or insufficient performance naturally fall under the two-year guarantee of proper functioning, for two years.

But where the failure of the boiler leaves the dwelling without any heating or hot water, the situation changes in nature. A dwelling without heating in winter is regarded as unfit for its purpose. In that case, the case law of the Cour de cassation accepts that the ten-year guarantee applies to an item of equipment, even a separable one, where its malfunction renders the structure unfit for its purpose. The ten-year guarantee for a boiler is therefore not excluded as a matter of principle: it depends on the seriousness of the loss of use.

This distinction is decisive in practice. If the defect occurs three years after acceptance, the two-year guarantee has expired: only the ten-year classification, based on unfitness for purpose, still makes it possible to obtain redress. Hence the importance of documenting the consequences of the breakdown precisely (statements, temperature readings, total absence of heating).

The double-glazed window, depending on whether it jams or leaks

The ten-year guarantee for a double-glazed window follows exactly the same reasoning. Joinery is separable equipment: its operating defects, a casement that sticks, a faulty opening mechanism, a seal that peels away without any effect on habitability, fall under the two-year guarantee for two years.

On the other hand, as soon as a defect in the fitting or design of the window causes water ingress inside the dwelling, we are back to the logic of waterproofing. Double glazing that lets water in and damages the walls impairs habitability and falls within the ten-year guarantee. Likewise, permanent condensation inside the glazing reflecting a total loss of insulation, if it makes certain rooms unusable, may fall within the ten-year guarantee.

The common thread is the same for the boiler and for joinery: it is not the nature of the equipment that decides, but the seriousness of its consequences for the normal use of the property.

How to trigger the right guarantee, and in the right order

The first step is to identify the date of acceptance and to calculate the three time limits. A defect discovered eight months after acceptance can be claimed under the completion guarantee, which is often the quickest route because it does not require the seriousness of the defect to be classified.

After one year, the defect must be classified in order to choose between the two-year and the ten-year guarantee. This is where the essential point is decided: a wrongly classified defect, presented as a matter of proper functioning when it renders the dwelling unfit for its purpose, exposes the client to an out-of-time claim if the two-year guarantee has already expired. In case of doubt, it is better to rely on the ten-year guarantee as the principal claim and on the two-year guarantee in the alternative.

As to procedure, the client first sends the builder a formal notice by registered letter with acknowledgement of receipt. For the ten-year guarantee, it notifies the claim to its structural damage insurer, which has time limits set by law to appoint an expert and to decide whether it will cover the loss. This insurance allows rapid advance financing of the works, without waiting for the court to identify the party responsible. In parallel, an expert report, whether out-of-court or court-ordered, is almost always necessary to establish the ten-year character of the defect. The steps of this process where the builder is a craftsman, with a model letter, are set out in our article on bringing a ten-year guarantee claim against a craftsman.

A final point to watch: the guarantee periods are periods for bringing an action. It is not enough to notify the defect; legal proceedings must have been commenced, or an agreement obtained, before the period expires. A writ of summons in summary proceedings (référé) for the appointment of an expert usefully interrupts the limitation period and secures the remedy.

Conclusion: reason by the seriousness of the defect, not by the nature of the equipment

The framework for reading the construction guarantees is not a fixed classification by type of equipment. It is a cascading analysis based on date and seriousness. During the first year, the completion guarantee covers everything that is notified. Beyond that, the question is never "is it a boiler, a window, a roof?" but "does this defect compromise soundness or render the property unfit for its use?". If so, the ten-year guarantee applies, with ten years of protection. If not, and if it is a separable item of equipment that works badly, the two-year guarantee applies, with two years.

The position taken in this guide is clear: faced with a waterproofing defect, a boiler that leaves the dwelling without heating or double glazing that lets water in, the ten-year guarantee, the longest and the best insured, should be considered first, and the two-year guarantee should be reserved for malfunctions with no effect on habitability. Under-classifying a defect is the most costly mistake, because it loses the benefit of the ten-year period.

Before taking any step, find the acceptance report, check the exact date, have the defect recorded by a professional who will document its effect on the use of the property, and notify the claim to your structural damage insurer without delay. If in doubt about the classification, have the file analysed before the shortest period expires: that will determine all of your remedies.

Frequently asked questions

What is the difference between the ten-year and the two-year guarantee?

The ten-year guarantee (Articles 1792 and 1792-2 of the French Civil Code) covers, for ten years, defects that compromise the soundness of the structure or render it unfit for its purpose, including items of equipment that cannot be separated from it. The two-year guarantee of proper functioning (Article 1792-3) covers, for two years, only separable items of equipment that cease to work without making the property uninhabitable. The dividing criterion is seriousness: impairment of soundness or of use for the ten-year guarantee, a simple malfunction of replaceable equipment for the two-year guarantee.

Is a waterproofing defect covered by the ten-year guarantee?

Yes, in the vast majority of cases. A waterproofing defect that causes water ingress renders the dwelling unfit for its purpose, which triggers the ten-year guarantee under Article 1792 of the French Civil Code for ten years from acceptance. This applies to leaks through the roof, a terrace or a façade, but also to water entering through badly fitted joinery, where habitability is affected.

Is the boiler covered by the ten-year guarantee?

It depends on the consequences of the breakdown. A boiler is separable equipment falling in principle under the two-year guarantee (two years). But if its failure leaves the dwelling entirely without heating and hot water, the property becomes unfit for its purpose and the Cour de cassation then accepts that the ten-year guarantee applies, even to separable equipment. The ten-year guarantee for a boiler is therefore not automatic: it requires showing a serious loss of use.

Is a double-glazed window guaranteed for ten years?

Not systematically. A defect in the mechanism or opening of a window falls under the two-year guarantee of proper functioning (two years). On the other hand, if the double glazing lets water through and causes water ingress, or loses its insulation entirely to the point of making rooms unusable, the ten-year guarantee for a double-glazed window may apply for ten years, because the defect renders the property unfit for its purpose.

From when do the construction guarantees run?

The three guarantees (completion, two-year, ten-year) run from the same date: acceptance of the works, evidenced by a signed and dated report. The completion guarantee lasts one year, the two-year guarantee two years and the ten-year guarantee ten years from that date. Without acceptance, these statutory guarantees cannot be relied on, hence the importance of formalising this act.

What should I do if a defect appears after one year and I do not know which guarantee to rely on?

The defect must be classified by its seriousness. If it compromises soundness or habitability, rely on the ten-year guarantee. If it is a separable item of equipment working badly without making the property uninhabitable, rely on the two-year guarantee, provided you are still within the two-year period. In case of doubt, it is better to rely on the ten-year guarantee as the principal claim and on the two-year guarantee in the alternative, and then have an expert report ordered to resolve the question.

Is structural damage insurance compulsory and what is it for?

Yes, structural damage insurance is compulsory for the client under Article L. 242-1 of the French Insurance Code. It makes it possible to obtain advance financing of repairs falling under the ten-year guarantee without waiting for a court to identify the party responsible. In the event of a claim, the insurer appoints an expert and decides on cover within time limits set by law, which considerably speeds up the repair of serious defects.