Carrez law diagnosis

What is the Loi Carrez diagnosis?


You want to sell a flat or a home in a condominium? You are obliged to inform the future buyer about the private living area.

Your AOD agency offers to carry out a Loi Carrez diagnosis to accurately measure the private surface in square metres (m2) of your property.

By definition, The private surface is an "official" surface area different from the living area.

The loi-Carrez diagnosis (law n° 96-1107 of 18 December 1996) is mandatory when selling a flat or a condominium. This also applies to new houses or already built.

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The Loi Carrez diagnosis, why should it be measured?


Mandatory in France since 1996Measuring Carrez law was established to protect the interests of future purchasers of a property when it is part of a lot or fraction of a lot in a co-ownership.

This diagnosis must be communicated to the buyer as soon as the compromise is signed

Which properties are affected?


In France, all sales of condominiums are mandatory since 18 December 1996.

This measurement calculation must be carried out if the surface area of the dwelling is greater than or equal to 8m2 :

  • Grouping of premises or flats or studios in a building
  • Clustering of premises or houses or studios in a housing estate

These accommodations can be:

  • for residential use
  • for commercial use
  • for professional use

Is the Loi Carrez diagnosis mandatory for all property sales?


The following are exempt from carrying out a Loi Carrez diagnosis:

  • The detached houses
  • Sales of building land
  • all lots under 8 m2
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What is the difference with the Boutin Law diagnosis?


The difference between these two diagnoses is the method of calculating the surface area: the Boutin Law diagnosis refers to the habitable surface area (rental) and the Carrez Law diagnosis refers to the private surface area (co-ownership sale).

This difference in the results of the measurement is due to the fact that the Carrez Law measurement takes into account the surface area of certain parts attached to the dwelling, whereas the Boutin Law measurement only adds the converted attic.

The living area will therefore always be less than the private area.

To put it simply, the Loi Carrez diagnosis is reserved for condominium sales and the Loi Boutin diagnosis is for rentals.

Who should carry out the Loi Carrez measurement?


Although the law does not require certification to carry out this diagnosis, the use of a certified professional is a guarantee of an accurate measurement.

It should be noted that in the event of a dispute, the seller of the property or the agent appointed by him to carry out the sale on his behalf will be held liable.

All our certified property diagnosticians are insured to protect you in the event of a measurement error.

What is the content of the Loi Carrez diagnosis?


Our real estate diagnostician measures the private surface of your property using a laser rangefinder to obtain a measurement that is in line with reality.

To obtain an accurate estimate, he will have to deduct the following areas:

  • The walls
  • Partitions
  • Sheathing
  • The stairs
  • Door and window openings
  • Cupboards
  • The reduced

Our property diagnostician will not take this into account:

  • Parts of the dwelling with a ceiling height of less than 1.80m
  • The cellars
  • Garages
  • The boxes
  • Parking spaces.
  • Mezzanines with a ceiling of less than 1m80 and less than 8m2)
  • Stairs and stairwells
  • Sheathing
  • Open balconies and terraces

How long is it valid?


The Carrez law surface measurement remains valid without time limitation as long as the co-ownership lot has not been transformed (extension, installation or removal of partition walls, etc.).

Why repeat this diagnosis before a sale or after a purchase?


There may well have been a mistake in the previous Loi Carrez diagnosis in terms of measurement or an inaccuracy in the calculation made by the property diagnostician or the owner himself.

Consequently, we strongly advise you to have one of our professional diagnosticians carry out the measurement of your property even if no changes have been made.

Indeed, if the previous certificate If a Loi Carrez diagnosis was produced more than one year ago, the only liability in the event of a dispute will be that of the seller and not the certified professional.

Does the absence of a Loi Carrez diagnosis lead to sanctions?


The Carrez law diagnosis must be attached to the DDT (technical diagnosis file) which accompanies the compromise or the deed of sale.

The buyer has the right to request the cancellation of the sale of the property within one month after signing.

The calculation of the surface area of my property is inaccurate, what recourse do I have?

In case of an error in the calculation of the surface area (at least 5% to the disadvantage of the buyer), you can claim compensation:

  • Or by cancelling the sale of the property. The request must be made within 1 month from the date of signing the final deed of sale.
  • Or by obtaining a reduction in the selling price.

However, this request must be made within 1 year of the signing of the deed of sale in order to obtain a price reduction in the event of an error of measurement (Article 1622 of the Civil Code).

Your AOD real estate diagnostician, to secure your real estate transactions

Do you need a property diagnosis for the sale or rental of your property? 

Our real estate diagnosticians are certified, insured and regularly trained remain at your service!

What are the regulatory texts?


How much does it cost to measure the Carrez Law?


The price varies according to the surface area of the property and its annexes. It is degressive if you have several property diagnoses carried out at the same time (such as the DPE diagnosis or the lead diagnosis, for example).

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