A court-ordered building expert assessment: what awaits you
A court-ordered expert assessment is an investigation ordered by the judge (Grasse, Nice, Toulon or Draguignan judicial courts) to establish the technical facts before judgment. Received a bailiff’s summons? The court-appointed expert will lead the visit. You have an absolute right to be assisted by a supporting expert (whom you choose and pay for) to defend your interests, challenge the findings and sign under reservation. The standard sequence: reading of the mission, site visit, contradictory draft report, technical meeting, final report to the judge.
Why you need to act quickly after the summons
The summons sets a visit date fixed by the court: it is not negotiable. You typically have 10 to 15 days to prepare your file and find a supporting expert (Cassini replies within 24 working hours). Waiting means losing:
- the ability to gather witness accounts: neighbours, tradespeople, the previous owner;
- original documents: invoices, insurance policies, correspondence, dated photographs;
- the time to build a counter-analysis: cracks measuring 2 mm on a crack gauge, not 5 mm to the naked eye;
- the balance of power at the visit: facing the court-appointed expert alone puts you at a disadvantage.
The start of the court term (September-October) concentrates the summons lists: overloaded experts accept fewer postponement requests. Acting within the first few days maximises your preparation.
Court-appointed expert vs. supporting expert: the two roles
The court-appointed expert (named by the judge) must be impartial, under Article 237 of the Code of Civil Procedure. They observe, measure, document. Their written mission fixes the scope (for example: “record the condition of the cracks and whether they are attributable to a construction defect”). Their report is addressed to the court, not to you.
The supporting expert (your choice) works for you. They attend the visit, ask questions, note discrepancies, and help you sign draft reports “under reservation” so that inaccurate measurements are not validated. Their role is not to judge, but to make sure your observations are recorded. You may also file written observations or a counter-report with the court after the assessment.
How a court-ordered building expert assessment unfolds
Stage 1: the visit and the reading of the mission
The court-appointed expert reads out the court’s terms of reference. Listen carefully: this fixes the limits of the investigation. If the dispute concerns roof waterproofing but the mission also mentions “foundations”, that matters. The supporting expert notes any silence or imprecision in the mission.
Stage 2: the on-site examination
The expert uses their instruments (laser level, thermal camera, hygrometer, anemometer, crack gauge, adhesion tester, inclinometer). They photograph, measure and ask questions. You and your supporting expert are present and may request clarifications. Never admit fault: “I didn’t maintain the roof” is an admission that will follow you to trial.
Stage 3: the contradictory draft report
A few days or weeks later, the expert circulates a draft report. This is your critical window: you can propose corrections, further measurements, observations. Sign “under reservation” if it contains inaccuracies (“crack estimated at 3 mm” when your gauge reads 1.5 mm). The reservations are attached to the final report.
Stage 4: the closing meeting (optional but common)
The court-appointed expert, the parties (you, the other side, your advisers) and the supporting experts meet. This is the technical debate: here, Cassini’s measurements (thermal camera, hygrometer) can contradict first impressions. Disagreements must be documented in writing.
Stage 5: the final report
The court-appointed expert files the report with the court. It lists the measurements, photographs and observations – including your reservations. The court relies on it to decide: it is not a verdict, but strong evidence.
How to prepare your file before the visit
Gather within five days of the summons:
- dated photographs: sketches of the cracks, photos with EXIF dates, general views of the property;
- invoices and estimates: repair works, maintenance, earlier surveys;
- handover reports (procès-verbaux de réception) for new or renovated works, evidencing when defects were first recorded;
- correspondence: emails, registered letters to the contractor mentioning the defect;
- witnesses: names and contacts of neighbours, former owners, companies that noted the defect;
- insurance documents: check whether your liability policy or the contractor’s ten-year (décennale) insurance covers the claim.
Bring all of this to Cassini at the first consultation: we structure your technical case before the expert visit.
Who pays what: the exact rules
Hidden defects (Article 1641 of the Civil Code)
You bought the property and discovered a defect afterwards (structural crack, water ingress, rising damp). The seller answers for hidden defects for two years from discovery (Article 1648). This is contractual liability: the buyer can seek rescission of the sale or a price reduction (Article 1644). The court-ordered assessment confirms the defect and that it predated the sale.
Construction defects and the ten-year warranty (Article 1792 of the Civil Code)
A defect revealed within 10 years of handover falls under the perfect completion warranty (1 year), the two-year warranty, or decennial liability (10 years) depending on whether it affects structural integrity or comfort. The contractor, project manager or company (depending on the contract) pays. Cassini establishes that the defect predated handover.
The buyer’s own liability (post-sale or poor maintenance)
If the assessment concludes that you failed to maintain the property (roof left uncleaned, blocked gutters, water ingress through lack of upkeep), liability falls on you. Avoid admitting this at the visit: let the expert reach a conclusion – and let your supporting expert challenge it with measurements if it is wrong.
How Cassini works: protocol and instruments
Cassini Expertise is not the judge; we are the building expert who assists the summoned party. Our protocol:
Preparation (Day 0 to Day 5)
- Meeting at our Antibes office: full review of the file;
- measurement of visible defects with a digital crack gauge (±0.1 mm accuracy);
- infrared thermal imaging (thermal bridges, hidden damp);
- damp readings with a hygrometer (rising damp, old infiltration);
- angles and tilts with an inclinometer (settlement, structural lean);
- surface flatness with a laser level.
During the expert visit (Day 10 to Day 20)
- we attend the visit and record the court-appointed expert’s observations;
- we measure independently with our own instruments;
- we log every discrepancy (a crack measured at 2 mm that the expert describes as “5 mm”);
- we decline to sign draft reports containing inaccuracies;
- we ask the technical questions the court-appointed expert must answer in the report.
After the visit (Day 25 to Day 35)
- analysis of the draft report: correcting measurements, adding reservations;
- drafting written observations for the court;
- structuring a technical counter-report where necessary;
- preparation for the closing meeting.
Which court, which visit
Your court depends on where the property stands:
- Grasse judicial court: Antibes, Cannes, Grasse, Vallauris, Biot;
- Nice judicial court: Nice, Saint-Laurent-du-Var, Villefranche-sur-Mer, Menton;
- Toulon judicial court: Toulon, Hyères, La Garde, Six-Fours;
- Draguignan judicial court: Draguignan, Fréjus, Saint-Raphaël.
On appeal: the Aix-en-Provence Court of Appeal. Cassini also intervenes at that stage for counter-assessments or written observations.
The four most common questions about court-ordered assessments
1. Can I refuse to attend the assessment I have been summoned to?
No. A court summons is binding. Failing to appear exposes you to damages. You may request a postponement from the judge (exceptional circumstances: hospitalisation, serious personal situation), but the court alone decides. Cassini prepares you for the visit from day one.
2. Can the court-appointed expert conclude that the defect is my fault?
Yes. Their report may state “lack of maintenance” or “construction defect”. It is then for the judge to adopt that conclusion – which is why the supporting expert matters: Cassini can demonstrate, with measurements, that maintenance is not the cause. For example, damp dated by hygrometric readings that points to a structural defect, not to neglect.
3. Must I sign the draft report?
Yes, but under reservation. Refusing to sign outright reads as bad faith. Instead, sign with the words “under reservation of” (for example: “under reservation of the crack measurement: the expert states 5 mm, our gauge reads 1.8 mm”). The reservation appears in the final report and protects your position.
4. Is a court-ordered assessment expensive for the party who requested it?
The court fixes the expert’s fee at the outset; it is advanced by the party who requested the assessment, then generally reimbursed by the losing party or shared according to the final judgment. The supporting expert, for their part, is paid by whoever instructs them: Cassini provides a free quote, replies within 24 working hours and delivers written work within 2 to 5 working days where the file allows.
Contact Cassini Expertise: assistance with court-ordered assessments in Antibes, Nice, Toulon
Received a summons for a building expert assessment in PACA? Cassini Expertise assists you immediately. We cover the Alpes-Maritimes (06), the Var (83) and the Bouches-du-Rhône (13), within the jurisdiction of the Grasse, Nice, Toulon and Draguignan judicial courts.
Phone 04 22 46 06 04 – make the appointment as soon as the summons arrives. The first days are decisive to structure your file and prepare you for the visit.
We analyse your situation, measure the defects, prepare your observations and attend the expert visit with you. Cassini applies a rigorous protocol: instrumented measurements, written report, follow-through to judgment.
Also read
- Counter-assessment for insurance claims in PACA
- Crack diagnosis RGA in the 06 and 83
- Building expert in Nice
Survey carried out by Frédéric Faucouneau, independent building expert – Antibes, Alpes-Maritimes (06), Var (83), Bouches-du-Rhône (13). Find out more
📅 Last updated 06/11/2026 - Cassini Expertise, independent building expert – departments 06, 83 and 13.