What is a real estate diagnosis?

The real estate diagnosis is a set of documents that is intended to inform a future buyer about the state of the housing he wishes to buy. In addition to avoiding disappointments after the signing of a deed of sale, this file makes it possible to control essential points of a home and its direct environment in order to guarantee the safety of all.

There are more than a dozen diagnoses. If they are mandatory, they must be carried out by a professional diagnostician certified by the French Accreditation Committee (COFRAC). Failure to comply with this rule results in penalties of up to € 1500 fine. In some cases, especially with regard to air noise, the owner can carry out the diagnosis himself. Be careful, however, not to disseminate erroneous information that could deceive the seller. He could then bring an action for damages and the cancellation of the sales contract.

Are they mandatory?

Real estate diagnoses have been mandatory since the Carrez Law came into force in 1997. They participate in the general obligation to inform a purchaser or tenant so that the latter has all the elements before committing. The owner must therefore constitute a technical diagnostic file (DDT) as soon as he plans to sell or rent his property. These documents will be useful at all stages of the real estate project. They will, in all cases, be annexed to the compromise in the case of a sale and to the lease in the case of a rental.

When to carry out real estate diagnostics?

The diagnoses are to be carried out from the moment you plan to sell or rent your property. Indeed, beyond the obligation to include them in the appendix of the promise or the sales agreement, they will sometimes be asked from the beginning of the visits by potential buyers or conscientious tenants. So do not wait until you find yourself with your back to the wall to call on a diagnostician to carry out these steps. You will be able to start your real estate project more serenely.

In addition, the validity period of real estate diagnoses varies depending on the case. We advise you to make them on the same date to guarantee the validity of your documents at the time of sale or rental of your property.

How long are real estate diagnoses valid

Each mandatory real estate diagnosis has its own validity period:

  • Validity of 6 months: state of risks and pollution (ERP), termites and merules in the context of housing located in municipalities covered by a prefectural order.
  • Validity of one year: finding of risk of exposure to lead (CREP) only if it is present (< 1 mg/cm2), without limits of validity if there is no trace.
  • Validity of 3 years: state of the gas installation, condition of the electrical installation and asbestos (if present, otherwise without limits of validity).
  • Validity of 10 years: energy performance diagnosis (DPE)
  • No fixed period for the state of air noise, so it is wise to renew it for each change of ownership.
  • No limit of validity concerning the Carrez law footage or the Boutin law living area. Be careful, however, to update these measures in case of work that changes the surface area of the housing.

Real estate diagnostics for sale

When selling a property, the owner is obliged to compile a file of real estate technical diagnostics to justify the conformity of the property placed on the market. These documents also make it possible to reassure a future buyer about the state of the property and its environment to avoid any unpleasant surprises. DDT can contain up to 11 diagnoses depending on the date of construction of the property, its location or its nature:

  • The energy performance diagnosis (DPE): it is the only diagnosis applied to all types of housing. It makes it possible to classify from A to G the energy consumption of the dwelling as well as its greenhouse gas emissions.
  • The finding of risk of exposure to lead (CREP) for dwellings built before 1949. It has no validity period unless the presence of lead is detected. In this case, it will have to be renewed every year.
  • The asbestos diagnosis for housing built before 1997. As with lead, it has no validity period unless asbestos is proven. It will then be necessary to renew the diagnosis every 3 years.
  • The condition of the gas installation and the electrical installation if they are more than 15 years old.
  • The state of risks and pollution (ERP) for housing located in a municipality covered by a prefectural order for the assessment of natural, mining, technological, seismic or radon-related hazards.
  • Diagnosis termites and other xylophagous insects if the dwelling is located in an area reported as infested or may be infested soon.
  • The diagnosis will be carried out if the dwelling is located in an area considered to be at risk by prefectural order.
  • Air noise if the accommodation is located in an area of exposure to airport noise.
  • The condition diagnosis of the sanitation facility if it is a detached house not connected to the public wastewater collection network.
  • The Carrez law footage if the housing is in a condominium. This measure does not take into account annexes such as cellars, parking spaces, garages, etc.

As part of the sale of an apartment, the owner must also provide the technical diagnosis of the condominium. This document gives an account of the general condition of the building in which the dwelling is located.

Real estate diagnostics for rental

When renting a property, the lessor must provide a file of real estate technical diagnostics (DDT) since Law No. 89-462 of 6 July 1989. The latter must accompany the lease at the time of signing. The file must include the following documents:

  • The energy performance diagnosis (DPE): it indicates the annual energy consumption of the dwelling as well as its greenhouse gas emissions.
  • The mention of the living space in the rental contract: mandatory since Law No. 2014-366 of 24 March 2014, known as the ALUR law. It concerns empty or furnished dwellings and includes floor space excluding walls, partitions, stairs, doorways and windows. It also excludes surfaces of less than 1.80 m.

In some special cases, other diagnoses must be added to the record:

  • The finding of risk of exposure to lead (CREP) for dwellings built before 1949.
  • The asbestos diagnosis for housing built before 1997. It is not mandatory, but must be able to be presented to the tenant if he so requests.
  • The state of risks and pollution for housing located in a municipality covered by a prefectural order for the assessment of natural, mining, technological, seismic or radon-related hazards.
  • The condition of the gas installation and the electrical installation if they are more than 15 years old.
  • Air noise if the accommodation is located in an area of exposure to airport noise.

How much does the real estate diagnosis cost and who pays for it?

Real estate technical diagnostics are the responsibility of the selling owner or lessor.

As part of a sale, the cost of a complete diagnostic file is generally between 400 € and 700 €. These costs relate to the condition of the property, its age, its location and its nature. Regarding the file of technical diagnoses in the context of a rental, it will be necessary to count between 150 € and 300 € depending on the case.

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