Pre-action report on defects: what it proves, what it does not replace (Article 145 CPC)

A project owner (maître d'ouvrage) who discovers cracks in a façade eighteen months after acceptance of the works, an investor who finds leaks in a freshly renovated office floor, an institutional landlord whose tenant relies on defects to suspend its rent: in all three cases the first decision is not legal, it is evidential. Should a commissaire de justice (bailiff) be brought in within fifteen days, a technical meeting with both sides present be organised with the contractors and their insurers, or summary proceedings for the appointment of an expert (référé-expertise) be issued straight away? The choice affects the future demonstration of the damage, the enforceability of the findings against the builders and, a point often overlooked, the fate of the limitation periods. This analysis compares the evidential value of the three steps, identifies the risks of unenforceability specific to each, and proposes a sequence before proceedings on the merits are issued.

The commissaire de justice's report: an act of preservation, not of demonstration

A purpose limited by law to material findings

The project owner's temptation is to obtain from a commissaire de justice a document that describes the defect and identifies its cause. The statute prohibits this. Article 1, II, 2° of Order No. 2016-728 of 2 June 2016 on the status of commissaires de justice authorises these public and ministerial officers to make, when appointed by the court or at the request of private persons, purely material findings, excluding any opinion on the consequences in fact or in law that may result from them.

The practical scope of this limit is considerable. A bailiff's report on defective works may describe a crack, measure its width, locate a trace of damp, note the absence of an item provided for in the contract, photograph a non-compliant substrate before it is covered over. It cannot conclude that the defect comes from a foundation fault, attribute liability to one trade package rather than another, or characterise the damage under Article 1792 of the French Civil Code. A report that strays into causal analysis is exposed to criticism from the opponent, and the disputed passage will be set aside.

Evidential force that is useful but relative

The same text provides that, except in criminal matters where they have the value of mere information, these findings are authoritative until proved otherwise. It is therefore not authority until a challenge for forgery. The opposing contractor may contest the report by any means, for example by producing its own surveys, a record of acceptance without reservations or earlier site photographs.

This relative evidential force is nonetheless superior to that of a photographic record made by the project owner or by its project manager (maître d'œuvre). Above all, it has a decisive advantage in terms of time: it fixes a state of affairs at a certain date. In defects litigation, the date of the findings often determines the outcome, whether the aim is to show that the defect was apparent at acceptance, that it came to light afterwards within the meaning of Article 1792-6 of the French Civil Code, or that it worsened between two phases of works.

The report made without the other side present and the risk of challenge

A commissaire de justice's report on defects is, by its nature, a unilateral act: it is drawn up at the request of one party. Under Article 1358 of the French Civil Code, except where the law provides otherwise, proof may be given by any means, so that its admissibility raises no difficulty. The difficulty lies elsewhere, in Article 16 of the French Code of Civil Procedure: the judge may rely on documents produced by the parties only if they have been able to discuss them in adversarial proceedings. A report put before the court and discussed by the opponent meets that requirement; it nevertheless remains a document whose value is measured by what the opponent can set against it.

In practice, the most effective lever is to summon the contractors and the project manager to the inspection, by registered letter with acknowledgment of receipt, stating the date and purpose of the operation. Their presence, or their absence after a proper summons, radically changes the nature of the later debate on the enforceability of the findings.

Amicable expert inspection with all sides present: speed of execution, evidential fragility

What an amicable expert inspection really produces

Where the commissaire de justice stops, the amicable inspection with all sides present begins: analysis of causes, attribution of the defects to the various parties involved, costing of the remedial works, proposal of a repair protocol. It is generally conducted either by an insurance expert, or by a technical expert appointed by the project owner, or within meetings organised between the builders' insurers.

Its value is operational. For an investor whose asset must remain usable, obtaining within a few weeks a technical diagnosis and a repair quotation is worth more than a court report delivered eighteen months later. An amicable inspection also makes it possible to test the insurers' position before any litigation and to fix the scope of a settlement.

The tipping point: adversarial process actually organised

A report drawn up solely at the project owner's request, without the builders being present, is only one document among others. The case law has long held that the judge cannot base a decision exclusively on a non-judicial expert report made at the request of one party alone, while accepting that such a report, properly put before the court and subject to free discussion by the parties, may be taken into account as one item of evidence among others. The practical consequence is clear: an isolated amicable expert report, uncorroborated, is not enough to secure a judgment against a builder.

Hence the importance of setting up the adversarial conditions. Summoning each party in writing with reasonable notice, giving them the contract documents and the prior findings, recording their observations in the report, accepting the presence of their own technicians: these steps turn a unilateral document into one that is costly for the opponent to challenge. The model to follow is that of Articles 160 and 276 of the French Code of Civil Procedure, which govern court-ordered expert inquiries, the first requiring the parties to be summoned by registered letter with acknowledgment of receipt or by handing a notice to their counsel, the second requiring the expert to take into consideration the parties' observations or complaints.

What an amicable expert inspection never produces

Two blind spots must be known to the decision-maker. First, no procedural sanction attaches to a builder's refusal to take part: a contractor that does not attend is exposed to nothing more than an argument of expediency. Second, and this is the point with the heaviest consequences, no text attaches to an amicable inspection, any more than to a commissaire de justice's report, the slightest interrupting or suspensive effect on time limits. A project owner who negotiates for fourteen months under the aegis of an insurance expert, letting the period under Article 1792-4-3 of the French Civil Code slip by, loses its claim without any rule coming to its rescue.

The référé-expertise under Article 145 of the Code of Civil Procedure: conditions, jurisdiction, effects

Legitimate reason and the link with Article 146

Article 145 of the French Code of Civil Procedure is the basis for summary proceedings to have an expert appointed in construction disputes:

If there is a legitimate reason to preserve or establish, before any proceedings, evidence of facts on which the outcome of a dispute may depend, legally admissible investigative measures may be ordered at the request of any interested party, on application or in summary proceedings.

Two conditions structure the application: the absence of proceedings on the merits already begun on the same subject matter, and the existence of a legitimate reason, that is, the plausibility of a future dispute whose outcome may depend on the facts to be established. The assessment of this legitimate reason is entirely a matter of case law and depends on the quality of the file presented to the judge.

A counter-intuitive consequence follows: a file that is too thin weakens the application, and so does a file that is already complete. Article 146 of the French Code of Civil Procedure provides that an investigative measure may be ordered on a fact only if the party alleging it does not have sufficient evidence to prove it and that in no case may an investigative measure be ordered in order to make up for a party's failure to produce evidence. The interplay of Articles 145 and 146 for measures in futurum is the subject of extensive case law that must be checked case by case; in practice, the applicant has an interest in showing that it holds serious evidence of the defect, but does not have the technical means to establish its cause and attribution. The commissaire de justice's report fulfils exactly that function: it documents the legitimate reason without replacing the measure sought.

Article 263 of the same Code confirms this hierarchy: an expert inquiry is to be ordered only where findings or a consultation could not suffice to inform the judge. Where there are multiple, evolving defects involving several trade packages and several insurance policies, this showing raises no difficulty.

Territorial jurisdiction: the derogation specific to buildings

Decree No. 2025-619 of 8 July 2025, which came into force on 1 September 2025 and applies only to proceedings begun from that date, inserted rules of territorial jurisdiction into Article 145. The principle is one of option: the court that could hear the case on the merits or the court of the place where the measure is to be carried out. But the text adds a derogation that governs defects cases:

By derogation from the second paragraph, where the investigative measure concerns a building, the court of the place where the building is situated has sole jurisdiction.

There is therefore no choice for a defect affecting a built structure. Applying to the court of the builder's registered office, or to the one provided for in a jurisdiction clause in the contract, exposes the applicant to an objection of lack of jurisdiction and to the loss of several months, in a timetable where every month counts. For an investor holding a portfolio spread over several court districts, this rule requires as many sets of proceedings to be opened as there are sites concerned.

The application route: exceptional, and now bound by time limits

Article 145 allows the judge to be seized on application or in summary proceedings. An application made without notice is, however, not a convenience option. Article 493 defines it as a provisional decision made without the other side being heard in cases where the applicant is justified in not calling an opposing party, and Article 845, second paragraph, opens this route only for urgent measures where the circumstances require that they not be taken in adversarial proceedings. In construction, the situations are narrow: risk of evidence disappearing before a structure is covered over, access to site documents liable to be destroyed, recording a state of affairs before a third-party contractor intervenes.

Two recent developments must be built into the timetable. First, Article 495 of the French Code of Civil Procedure, in the version resulting from Decree No. 2026-683 of 27 July 2026, in force on 1 October 2026 and applicable to decisions made from that date, provides that on pain of lapse raised of the court's own motion, an order made on the basis of Article 145 is to be executed within three months of its date, unless the judge sets a different period for execution. Obtaining an order and waiting for the technician to become available is no longer without consequence.

Second, Article 496, in the same version, binds the procedure for challenging the order (référé-rétractation): on pain of inadmissibility, where the order made on the basis of Article 145 has been served, the matter is brought before the judge within one month of the date of service. Service of the order thus becomes a strategic act for the applicant, since it starts the period for challenge. Article 497 also preserves the judge's power to modify or withdraw the order, even if the court on the merits is seized of the case. The application over time of these new paragraphs to orders made before 1 October 2026 requires a full reading of the decree's transitional provisions.

The effect on time limits: the decisive argument

This is where the référé-expertise stands irreducibly apart from the amicable routes. Article 2241 of the French Civil Code provides that a claim brought before the court, even in summary proceedings, interrupts the limitation period as well as the time bar, including where it is brought before a court that lacks jurisdiction. Article 2239 adds that limitation is suspended when the judge grants an application for an investigative measure made before any proceedings, the period starting to run again for a duration that may not be less than six months, from the day the measure was carried out.

Applied to construction, this mechanism secures a timetable that would otherwise be untenable. Liability actions against builders and their subcontractors are time-barred, under Article 1792-4-3 of the French Civil Code, ten years from acceptance of the works, apart from actions governed by Articles 1792-3, 1792-4-1 and 1792-4-2. Personal actions are subject to the five-year period under Article 2224, from the day the holder of the right knew or should have known the facts enabling it to be exercised. A court-ordered expert inquiry ordered in the ninth year and then carried out over eighteen months leaves a residual period in which to issue proceedings on the merits; the same sequence conducted amicably leaves the project owner time-barred.

One difficulty remains that the texts read do not resolve: the interrupting and suspensive effect is assessed in respect of the parties brought into the summary proceedings. A builder or an insurer called into the operations late may therefore plead a different position as to time limits. The operational consequence is simple: identify in the originating application all the parties involved, namely the contractors, subcontractors, project manager, technical control office and ten-year liability insurers, and promptly seek extensions of the operations by joint order for parties revealed during the inquiry. The conduct of the operations, from the deposit to the expert's comments and then the challenge to the draft report, is set out in our article on court-ordered property expert inquiries.

The operational risks of the référé-expertise

Three points of vigilance should be anticipated before the measure is triggered.

• The deposit: Article 271 of the French Code of Civil Procedure provides that failing payment of the deposit within the time and in the manner prescribed, the appointment of the expert lapses, save for an extension or relief from lapse granted by the judge at the request of a party relying on a legitimate reason. A diary oversight destroys the measure and the time benefit sought.
• Enforceability: the operations are usefully enforceable only against parties properly called. A report delivered without a subcontractor having been brought in exposes the applicant to having to repeat all or part of the measure.
• The weight of the report: Article 246 of the French Code of Civil Procedure recalls that the judge is not bound by the technician's findings or conclusions. A favourable report is not a title; it is a key document that must still be converted into a judgment.

Sequencing the three steps: a decision timetable

Before and at the time of acceptance

Acceptance is, under Article 1792-6 of the French Civil Code, the act by which the project owner declares that it accepts the works with or without reservations, and it is in any event, made with both sides present. At this stage, the relevant tool is the commissaire de justice's report, intended to document apparent non-conformities before they are covered over, or to secure the material reality of the reservations where the contractor disputes the record of acceptance. The report here serves as a protective measure in the economic sense of the term: it fixes the state of the works at a date that no one will be able to reconstruct afterwards.

During the completion warranty year

Article 1792-6 requires the contractor, for one year from acceptance, to make good all defects notified either by means of reservations noted in the record of acceptance, or by written notification for those revealed after acceptance. Written notification is therefore the condition for entering into the warranty. A commissaire de justice's report annexed to the notification secures both the date of revelation and the description of the defect. The amicable inspection with all sides present finds its natural ground here: the aim is not yet to attribute liability, but to obtain repair, the text providing that, failing agreement or in the event of non-performance within the period set, the works may, after a formal demand that has remained without result, be carried out at the cost and risk of the defaulting contractor. On the formal demand and on carrying out repairs at the builder's cost and risk, see our analysis of the completion warranty (garantie de parfait achèvement).

Where the defect is structural or positions harden

Once the defect compromises the soundness of the structure or makes it unfit for its purpose within the meaning of Article 1792 of the French Civil Code, several parties pass the cause back and forth, or an insurer disputes its cover, the amicable inspection has reached its limit. The référé-expertise becomes the structuring step, for three cumulative reasons: it imposes the adversarial process, it makes the operations enforceable against those called to them, and it acts on time limits.

The link with structural damage insurance (dommages-ouvrage)

Where a structural damage insurance policy (dommages-ouvrage) has been taken out, Article L. 242-1 of the French Insurance Code imposes a strict timetable on the insurer: at most sixty days from receipt of the claim notification to notify its decision on whether the cover is engaged in principle, ninety days from the same date to make an offer of indemnity, if need be an interim one, and fifteen days for payment in the event of acceptance. In the event of exceptional difficulties, an additional period, subject to the insured's express acceptance, may not exceed one hundred and thirty-five days. Where the insurer fails to meet one of these periods or makes a manifestly insufficient offer, the insured may, after notifying the insurer, incur the expenses necessary for the repair, the indemnity then being increased by operation of law by interest at twice the statutory rate. The claim notification that starts these periods and the sanction for the insurer's silence are dealt with separately in our article on making a claim under structural damage insurance.

This timetable is a lever for negotiation, not an alternative to a court-ordered expert inquiry. The claim notification must be sent without delay, with the commissaire de justice's report attached. But applying to the summary proceedings judge (juge des référés) remains indispensable if the insurer's position hardens or if the cause of the defects implicates several builders.

The recurring errors that cost the case

Four patterns recur systematically in defects cases that are lost or weakened.

• Having the defects repaired before any findings are made: the repair destroys the evidence and leaves the project owner unable to demonstrate the initial extent of the damage.
• Asking the commissaire de justice for a technical assessment: the report goes beyond its statutory purpose and its most useful passage is set aside.
• Negotiating amicably beyond what is reasonable: no text attaches suspensive effect to discussions, and an opponent who drags matters out does not always act in good faith.
• Issuing summary proceedings against an incomplete set of defendants: the operations will have to be extended, with cost, delay and uncertainty as to the effect of Articles 2239 and 2241 of the French Civil Code in respect of parties called in late.

Conclusion: a sequence, not an alternative

Putting the question as an exclusive choice is the first error of judgement. The three steps have neither the same function nor the same procedural yield. The commissaire de justice's report preserves the material reality of the defect at a certain date and is authoritative until proved otherwise, but says nothing about the cause. The amicable inspection with all sides present produces the technical diagnosis and opens negotiation, but binds no one and protects no time limit. Only the référé-expertise under Article 145 of the French Code of Civil Procedure combines organised adversarial process, enforceability and an effect on limitation, at the price of a delay, a deposit and a report that does not bind the judge.

The effective sequence is therefore cumulative: an immediate report to fix the facts, written notification to the builder to preserve the completion warranty and a claim notification to the structural damage insurer, an attempt at amicable inspection strictly limited in time, then an application to the summary proceedings judge before the court of the place where the building is situated, which has had sole jurisdiction since Decree No. 2025-619 of 8 July 2025, with the set of defendants settled as soon as proceedings are issued.

Before any repair of a defect and before any technical meeting with the contractors, have your adviser set down in writing two dates: the limitation date applicable to each ground envisaged, and the date beyond which amicable discussion will be broken off in favour of summary proceedings. It is this timetable, and not the quality of the technical report, that determines the value of your position.

Frequently asked questions

Is a commissaire de justice's report enough to prove a defect before the court? No. The commissaire de justice's findings are, under Article 1, II, 2° of Order No. 2016-728 of 2 June 2016, purely material, excluding any opinion on the consequences in fact or in law. They are authoritative until proved otherwise, except in criminal matters where they count as mere information. The report therefore establishes the existence and apparent state of the defect at a certain date, but neither its cause nor its attribution to a particular builder. It prepares the référé-expertise, it does not replace it.

Which court should be applied to in summary proceedings for an expert where the defects affect a building? Since Decree No. 2025-619 of 8 July 2025, applicable to proceedings begun from 1 September 2025, Article 145 of the French Code of Civil Procedure provides that, by derogation from the option open to the applicant, where the investigative measure concerns a building, the court of the place where the building is situated has sole jurisdiction. There is therefore no choice in defects cases. A jurisdiction clause in the works contract does not allow this to be departed from for the investigative measure.

Does an amicable expert inspection interrupt the ten-year limitation period? No. Article 2241 of the French Civil Code attaches the interrupting effect to a claim brought before the court, even in summary proceedings, and Article 2239 attaches the suspensive effect to the judge's decision granting an application for an investigative measure made before any proceedings. No text confers such an effect on an amicable report or on an inspection organised between the parties or their insurers. Since actions against builders are time-barred ten years from acceptance under Article 1792-4-3, prolonged negotiation without applying to the court runs an uncovered risk of being time-barred.

Can an expert inquiry be obtained on application, without calling the builder? Only in narrow cases. Article 493 of the French Code of Civil Procedure defines an order on application as a decision made without the other side being heard in cases where the applicant is justified in not calling an opposing party, and Article 845 requires that the circumstances call for the absence of adversarial process. Since Decree No. 2026-683 of 27 July 2026, in force on 1 October 2026, Article 495 also requires that an order based on Article 145 be executed within three months of its date, on pain of lapse raised of the court's own motion, unless the judge sets a different period.

Within what period can the builder challenge an order on application obtained against it? Article 496 of the French Code of Civil Procedure, in the version in force since 1 October 2026, provides that on pain of inadmissibility, where the order made on the basis of Article 145 has been served, the matter is brought before the judge within one month of the date of service. Service of the order therefore becomes an act of procedural strategy for the applicant. Article 497 also allows the judge to modify or withdraw the order, even if the court on the merits is seized.

What is the risk if the expert's deposit is not paid on time? Article 271 of the French Code of Civil Procedure provides that, failing payment of the deposit within the time and in the manner prescribed, the appointment of the expert lapses, unless the judge, at the request of a party relying on a legitimate reason, decides to extend the period or to relieve the party from lapse. Lapse destroys the operational benefit of the measure and requires the procedure to be started again. The deposit must therefore appear in the monitoring timetable in the same way as service of the order.

Is the court-ordered expert report binding on the court on the merits? No. Article 246 of the French Code of Civil Procedure provides that the judge is not bound by the technician's findings or conclusions. Article 263 also recalls that an expert inquiry is to be ordered only if findings or a consultation could not suffice to inform the judge. The report is the central document in the file, but a judgment still requires a legal demonstration built on the relevant grounds of liability, in particular Articles 1792 et seq. of the French Civil Code.