Carrez floor area (surface Carrez)

The surface Carrez (Carrez floor area) is the private floor area of a lot in a copropriété (French co-ownership of flats), as the law requires it to be stated in every preliminary contract and every deed of sale. It corresponds to the floor area of enclosed and covered premises, after deduction of the areas occupied by walls, partitions, steps and stairwells, ducts, and door and window openings. Parts of premises with a ceiling height below 1.80 metres are not counted, nor are lots or fractions of lots of less than 8 m². Cellars, garages, parking spaces, balconies and terraces are excluded.

Its importance comes from its sanction. If the actual floor area is more than one twentieth (5 %) below that stated in the deed, the buyer may claim a price reduction in proportion to the shortfall, within one year of the notarial deed. Conversely, a surplus gives rise to no additional price.

Where the rule comes from

Article 46 of the Law of 10 July 1965, inserted by the Law of 18 December 1996 (known as the Carrez Law), lays down the obligation to state the area and the action for a price reduction. The decree of 23 May 1997 sets the method of measurement. The Charte de l’expertise en évaluation immobilière (the French property valuation charter) restates these rules in Title III, § 3.3.5, and stresses that this private floor area is very close to the habitable floor area and to the net usable area without being the same as either. The law applies only to co-ownership lots; a detached house outside a co-ownership is not subject to it.

In a valuation report

I am not the measurer: the area certificate is drawn up by a surveyor or a géomètre. My role comes in when the shortfall has been established and its consequences must be quantified. The price reduction is calculated pro rata to the missing area on the sale price, which requires no expert work. On the other hand, when the buyer sues a professional (surveyor, architect, developer) for damages, or when the shortfall goes beyond a simple rule of three (a flat that has become unfit for its intended use), I assess the real loss: value of the property with the stated area, value with the actual area, loss of the chance to negotiate. For this I use comparables per m² and explain whether or not the market values every square metre in the same way.

Example

A flat sold for €240,000 with a stated Carrez area of 64 m². A new measurement establishes 59.8 m², a shortfall of 6.6 %, above one twentieth. Price reduction: 240,000 × 4.2 / 64 = €15,750. In a liability action against the surveyor, I compare the market value at 64 m² (€3,750 per m²) and at 59.8 m²: the local market prices small flats a little higher per m², and the real value comes to €228,000, a loss of €12,000, a figure distinct from the statutory reduction.

Not to be confused with

The habitable floor area (French Construction and Housing Code) also excludes unconverted lofts, basements, sheds, conservatories and parts below 1.80 metres, and applies to all dwellings, whether in co-ownership or not. The surface de plancher is a planning concept.