The Carrez surface (law of 10 July 1965) is the floor area of enclosed and covered premises, after deducting walls, partitions, stairs and door recesses. In a VEFA (off-plan) sale, it must be stated in the deed of sale. If it is more than 5% smaller than the surface announced, the buyer can obtain a proportional price reduction.
How is the Carrez surface calculated?
It does not include: exterior and interior walls and partitions, stairs and stairwells, door and window recesses, areas with a ceiling height below 1.80 m, unconverted attics, cellars, garages and parking spaces. Measurement must be carried out by a qualified professional (chartered surveyor) according to the NF P 04-501 standard.
Common developer errors
- Including the exterior walls in the calculation
- Including balconies and terraces (uncovered areas)
- Failing to deduct stairwell openings
- Announced surface = gross floor area instead of Carrez surface
What to do if the discrepancy exceeds 5%?
You have one year from the date of the notarial deed to take action. The price reduction is calculated proportionally: (actual surface / announced surface) x sale price. For example: 55 m² instead of the announced 60 m² → an 8.33% price reduction.
Carrez surface vs habitable surface: don’t confuse the two
The Carrez surface should not be confused with the habitable surface (Boutin law), used notably for rentals, nor with the floor area used in urban planning to calculate building rights. These three concepts follow different calculation rules, and the same property can show three different figures depending on the document consulted (deed of sale, lease, building permit).
Who can carry out a Carrez measurement?
Unlike the energy performance diagnostic, the law does not require specific certification for Carrez measurement: the notary, the estate agent or the seller can theoretically carry it out themselves. In practice, using an independent building expert or chartered surveyor greatly reduces the risk of error and later disputes, since liability for the measurement falls primarily on the seller in case of error.
Procedure in case of a dispute after the sale
- Contradictory measurement by an independent expert, compared with the surface stated in the deed.
- Formal notice sent to the seller (or developer in a VEFA sale) together with the measurement report.
- Amicable negotiation of the proportional price reduction.
- Legal action before the civil court if no agreement is reached, within one year of the notarial deed.
FAQ
Can the seller refuse a contradictory measurement? They can refuse it amicably, but a judge can order a judicial expert assessment if legal action is taken within the deadline.
Does the guarantee apply if the surface is larger than announced? No: the Carrez law only provides for a price reduction if the surface is more than 5% smaller. No increase is due if the actual surface is larger.
Cassini Expertise carries out contradictory measurements. Request a Carrez measurement →
📅 Updated on 14/08/2026 — By Cassini Expertise, independent building expert for the Alpes-Maritimes & Var. Free quote: 04 22 46 06 04.
To go further:
Frequently asked questions
How is the Carrez surface calculated in a VEFA sale?
The Carrez surface is calculated by measuring the floor area of enclosed and covered premises, after deducting walls, partitions, stairs and door recesses. In a VEFA sale, the calculation should be based on the developer’s plans, but it is advisable to have it checked by a professional at handover, as errors are common.
What is the common error in calculating the Carrez surface in a VEFA sale?
A common error is including areas where the ceiling height is below 1.80 metres, or failing to deduct the areas occupied by walls and partitions. Some developers may also calculate the surface based on the plans without accounting for actual differences during construction, which can lead to a price reduction.
Can I request a price reduction if the Carrez surface is smaller than stated in the VEFA contract?
Yes, if the actual surface is more than 5% smaller than stated in the contract, the buyer can request a proportional price reduction. It is important to have this difference confirmed by a professional (surveyor) and to act within the legal deadline, generally one year after signing the notarial deed.
Cassini Expertise
Expert du bâtiment indépendant — Antibes (06·83·13·40)
📅 Mis à jour le 25/09/2026 — Cassini Expertise, expert bâtiment indépendant (06·83·13·40).