What are the mandatory diagnostics ?

What are the mandatory diagnostic tests needed when selling?

Diagnostic tests were put into place as to help inform potential buyers of a property’s characteristics and conditions by certifying them by a certified third party. Since 2012, if you decide to sell your real estate asset you will be asked to compile a total of 9 diagnostic reports by the law.

Let’s dig into the different reports required by a property seller in France. 

Obligatory real estate diagnostic tests when selling

In France, as it is the case in the United Kingdom, sellers obliged to provide an Energy performance certificate for the property. It is the only diagnostic report that is systematically required. Regarding the other 8 mandatory reports, their delivery depends on the nature of the property, the year of construction and the house or flat’s geographical location. It is important to note that if a diagnostic report is missing or incorrect, the sale of a property can be cancelled or reduced, do not neglect them! 


1. The EPC (energy performance certificate) 

In France, this diagnostic contains information about a property’s energy consumption and its green gas emission. This diagnostic is being rolled out throughout Europe in recent years. It has a period of validity of 10 years and is required for all real estate properties.

If an EPC is based on incorrect (Deliberately or accidental) information, as a seller you risk a fine of up to 37500€ and 2 years in prison. 


The lead-safe certificate informs the buyer on the potential presence of lead in the old previous or preexisting paintwork. It is required for properties built before the 1/01/1949. If the report is negative (no lead detected) it has an unlimited period of validity whereas if the presence of lead is identified the lead-safe certificate will have to be updated on a yearly basis.

2. The lead-safe certificate


3. Asbestos inspection: 

This report allows for the buyer to be aware of materials containing asbestos in the property.  It compulsory for any house, flat and outbuildings which had its building report delivered before the 1st of July 1997. Its period of validity is unlimited.


This document is mandatory for any property located in a zone defined as infested by termites by a prefectural order. Its period of validity is 6 months

4. The termite diagnosis


5. The gas diagnostic:

The gas diagnosis estimates the condition and the gas installation. Required for all properties with a gas installation equipped 15 years before the date of sale or which has certificate of compliance dating back more than 15 years, it has a period of validity of 3 years. 


When the electrical installation diagnosis of a real estate asset dates back more than 15 years, it is compulsory. This diagnosis allows the buyer to verify the safety of the electrical installation. It is valid for 3 years. 

6. The eletrical installation diagnostic


7. The Sewer system report

For any property which is not connected to the public wastewater collection systems, owners are legally obliged to be equipped with their own independent installation. As to verify that it is working well, such properties are required to have an inspection done. The certificate has a period of validity of 3 years


Risks related to a house or flat, are detailed in a prefectural order visible at the relevant town hall, in which the concerned municipalities are indicated. If your asset is located in potential risk area, you as the owner are obligated to inform the buyer through this report of it. 

8. The natural, mining and technological risks diagnostic


9. The Carrez Law diagnostic

Since the 18th of December 1996, the Carrez Law sets out to protect buyers. To do so it compulsory for the seller to state the net surface unit of the property on every single document related to the selling of the house or apartment (area must be superior to 8 m2). In France, the measurement is that of the total floor area which means it does not take into consideration areas occupied by walls, building partitions, doorways, windows, stairs, stairwells and plinths.

The period of validity of the Carrez Law diagnostic is unlimited except if a new smaller measurement is noticed. 

Who establishes property diagnostic tests?

A certified diagnostician

In order to establish the technical diagnostics for your property (The Sewer system report and the natural, mining and technological risks diagnostic exempted), it is essential to call upon a certified consultant.  Do not forget that if a diagnostic report is missing or incorrect, the sale of a property can be cancelled or the price reduced, do not neglect them!

By visiting the website of the ministry in charge of the environment, you will be able consult the list of certified diagnostician located in the municipality or the surroundings.

It is important to note that the sewer system report is done by the public service for non-collective water treatment and that the natural, mining and technological risks diagnostic has to be provided by the seller (diagnostic available at the town hall).

How much costs the mandatory diagnostics?

Current costs

Rates are fixed by the diagnosticians and there are no restrictions, they are free to choose the price therefore we encourage you to shop around and compare prices before committing.

Moreover, prices are in function of the number of reports and the nature of your home: house or flat, surface, geographical location and year of construction.

For example, a studio flat built before 1949, the cost of the mandatory diagnostics will amount to 272€. For a flat with three rooms a kitchen constructed between 1949 and 1996, it will put back you 242€. For a house completed after 1997 the price will be 193€. (cf. diagram below).


How to get a free diagnostic for your house or flat

If you sign a 6 month sole selling rights agreement with Carmen, we grant you a free mandatory diagnostic.

If you prefer to grant us a 3 month sole selling rights agreement, we will provide you with our special negotiated prices.

CARMEN IMMOBILIER’s sole selling rights agreement has a number of other advantages; we award you with the possibility to have a professional photographer come and better showcase your house or flat. We also guarantee to offer your property on the diverse amount of different platforms that we take advantage from.

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