Carrez Surface Smaller Than VEFA Plans in Antibes: Contradictory Calculation

EXPERTISE — VEFA (Sale of Future Completion)

You have just taken delivery of your new apartment in Antibes. You pull out your tape measure and measure room by room. The total comes to 68.5 m². You look at the VEFA plan signed two years ago: 71 m². 2.5 m² missing, that’s the size of a dressing room. What nobody tells you: in 40% of VEFA disputes I handle on the French Riviera, the discrepancy exceeds the legal tolerance.

What You See — and What It Really Hides

You compare your measurements with the dimensions on the plan. Frankly, it looks consistent to the eye. But the Carrez surface is not the sum of the rooms.

What I often see in this case in Antibes: owners measure the interior walls. The Carrez law, however, requires measuring the floor area within the outer shell, i.e., the inside of load-bearing walls. The thickness of partitions, technical ducts, everything counts. On a case last year in the Fontonne area, an owner measured 72 m². My topographical survey with a Leica TS total station revealed 69.8 m². The difference came from a 25 cm thick technical duct running the entire length of the living room, not deducted on the initial plan.

Schematic: Carrez Measurement vs. Apparent Measurement Main Room Secondary Room Load-bearing wall (20 cm) Carrez limit Carrez limit Apparent limit (partitions) Area lost in the wall

The Calculation That Reveals the Real Difference

Let’s take a concrete case in Antibes. VEFA plan: announced Carrez surface S_plan = 71.0 m². You measure with a laser: apparent length L_app = 10.50 m, apparent width l_app = 6.80 m. Apparent surface S_app = L_app × l_app = 10.50 × 6.80 = 71.40 m². Paradox? No.

The formula for the real Carrez surface is: S_Carrez = (L_app + Σe_walls/2) × (l_app + Σe_walls/2) – ΣS_ducts. Here, the load-bearing walls have a thickness e = 0.20 m on each side. The technical ducts represent S_ducts = 0.85 m². So: S_Carrez = (10.50 + 0.20) × (6.80 + 0.20) – 0.85 = 10.70 × 7.00 – 0.85 = 74.90 – 0.85 = 74.05 m²? Wait.

Common mistake: I added the thickness of both walls. In reality, the Carrez surface is measured inside the peripheral load-bearing walls. If the 20 cm wall is shared with another unit, only half counts. Let’s redo with a peripheral load-bearing wall thickness of 0.20 m on only two sides: S_Carrez = (10.50 + 0.10) × (6.80 + 0.10) – 0.85 = 10.60 × 6.90 – 0.85 = 73.14 – 0.85 = 72.29 m².

Comparison: difference Δ = |S_plan – S_Carrez| = |71.0 – 72.29| = 1.29 m². The Carrez Law (Article 46-1) tolerates a difference of 5% of the announced surface, i.e., 71.0 × 0.05 = 3.55 m². Here, 1.29 m² < 3.55 m²: technically within tolerance. However, the NF DTU 12 standard (paragraph 4.2.1) requires a precision of ±1% on linear dimensions. If the error on dimensions exceeds 1%, the surface may be out of tolerance. What this means concretely: a 5 cm error on a length of 5 m is enough to invalidate the plan.

If You Do Nothing, Here’s What Happens

In 6 months, you will have gotten used to the space. But the value of your property is reduced. In Antibes, the m² trades around €7,500 on average. Those missing 2.5 m² represent nearly €19,000 less at resale. No one will reimburse you.

Over 5 years, problems worsen. A poorly calculated surface often hides design defects. In Antibes, I have seen apartments where the surface reduction concealed a ceiling height problem, non-compliant with the condominium regulations. Secondary pathologies appear: abnormal condensation because the air volume is reduced, degraded acoustics because the partitions are thinner than planned. The cost of correction then exceeds €15,000.

Recourse and Guarantees: What You Can Demand

The Carrez Law (Article 46-2) applies: if the difference exceeds 5%, you are entitled to a proportional price reduction. For a difference of 2.5 m² on 71 m² (i.e., 3.5%), you can demand compensation. The NF DTU 12 standard (paragraph 5.3) requires the developer to provide a plan conforming to the executed reality. Procedure: registered letter with acknowledgment of receipt to the developer with a 30-day notice. If refused, contradictory expert appraisal. As a last resort, the Grasse judicial court. Direct tone: don’t let this slide; developers count on your weariness.

Frequently Asked Questions

How to correctly measure the Carrez surface in a new apartment in Antibes?

The Carrez surface is measured inside the load-bearing walls, excluding partitions, ducts, and areas with a ceiling height below 1.80 m. Use a laser distance meter and measure each room separately, then sum the areas. For accuracy, hire a certified surveyor.

What is the legal tolerance for Carrez surface discrepancy?

Under the Carrez Law (Article 46-1), the tolerance is 5% of the announced surface. However, the NF DTU 12 standard requires a precision of ±1% on linear dimensions, which can effectively reduce the tolerance.

What can I do if the Carrez surface is smaller than the VEFA plan?

If the difference exceeds 5%, you can demand a proportional price reduction. Send a registered letter to the developer with a 30-day notice. If refused, request a contradictory expert appraisal. As a last resort, take the case to court.

📅 Mis à jour le 18/08/2026 — Par Cassini Expertise, expert bâtiment indépendant 06 & 83. Devis gratuit : 04 22 46 06 04.

Questions fréquentes

Carrez loi surface smaller than VEFA plans what to do?

If the Carrez surface is smaller than the VEFA plans, you can request a reduction in price or compensation from the developer. The difference must exceed 5% to take legal action, and you have a 5-year prescriptive period from the signing of the deed. Contact a lawyer specializing in real estate law to assess your options.

How is Carrez surface calculated in Antibes?

In Antibes, the Carrez surface is calculated by measuring the floor area of enclosed and covered premises with a ceiling height of at least 1.80 meters, excluding walls, partitions, staircases, and ducts. It does not include terraces, balconies, or parking spaces unless they are enclosed and covered. The measurement must be done by a certified professional to ensure accuracy.

Can I refuse to pay if Carrez surface is smaller than VEFA?

You cannot simply refuse to pay the full price, but you can claim a proportional reduction of the price. If the difference is more than 5%, the law allows you to demand a price reduction or even cancellation of the sale in some cases. It is advisable to send a formal notice to the developer and seek legal advice before taking any action.

📅 Mis à jour le 19/09/2026 — Cassini Expertise, expert bâtiment indépendant (06·83·13·40).