Mandatory Property Diagnostic: Complete List 2026

The technical diagnostic file is not an administrative formality that you put together the day before signing. It is a contractual document whose absence or expiry deprives the seller or landlord of the clause exempting them from liability for hidden defects, and opens the door to a price reduction or annulment. The difficulty lies less in the list of diagnostics than in two things: knowing which ones apply to your property, and monitoring validity periods that range from six months to unlimited.

What triggers the obligation

No property requires the full set of diagnostics. Three parameters determine the applicable list:

• The nature of the transaction. A sale and a lease do not call for the same file. Some diagnostics are common to both, others are specific to one of the two.
• The age of the property and its installations. The year of construction determines the asbestos and lead diagnostics; the age of the gas and electrical installations determines theirs.
• The location. Termites, dry rot, natural and technological risks depend on prefectural orders and municipal zoning.

This gives rise to a practical rule: the list is built property by property, never by copying the file of a neighbouring property.

Diagnostics in the case of a sale

The energy performance diagnostic. Valid for ten years. It has become the document with the heaviest consequences, because it no longer merely informs: it conditions the possibility of letting the property, and its rating has been enforceable since the reform that gave it binding force.

The energy audit. It is added to the performance diagnostic for sales of single-family houses and buildings under sole ownership classified in the lowest categories. The scope is being widened in successive stages: this is a point to check for the current year, as the timetable has been adjusted several times.

Asbestos. Required for properties whose building permit predates July 1997. A negative finding does not need to be redone; a positive finding requires periodic monitoring.

The lead exposure risk assessment. For dwellings built before 1949. Its validity depends on the result: unlimited if the finding is negative, only one year if it reveals a presence of lead above the threshold.

Gas and electrical installations. Mandatory as soon as the installation is more than fifteen years old. Validity of three years for a sale.

The risk disclosure statement. Natural, mining, technological, seismic, radon risks. Its validity is short — six months — and it is the diagnostic that expires most often between the preliminary sale agreement and the final deed.

Termites. Only in areas defined by prefectural order, with a validity of six months as well.

Non-collective sanitation. When the property is not connected to the public network, with a validity of three years.

Measurement. The private floor area in a co-owned building falls under the loi Carrez. Its validity is unlimited as long as no work changes the area, but an error of more than one-twentieth gives rise to a price reduction.

Diagnostics in the case of a lease

The file is shorter, and the validity periods differ — this is the most frequent source of error among landlords who reuse a sale file.

• The energy performance diagnostic, valid for ten years.
• The lead assessment, whose validity for a lease is six years if positive, unlimited if negative.
• The gas and electrical installation reports, valid for six years for a lease compared to three for a sale.
• The risk disclosure statement, always six months.
• The habitable floor area, within the meaning of the loi Boutin, distinct from the Carrez area.

The whole set is annexed to the lease. This annexation is not symbolic: it is what makes the file enforceable, and its absence can be argued in court. The electronic signature of a residential lease offers a concrete advantage here, by sealing the contract and its annexes into a single dated set, which can be shown not to have been reassembled afterwards.

The tipping point: energy decency

The energy performance diagnostic has changed in nature. It no longer simply informs the buyer or tenant: an insufficient rating purely and simply prohibits letting the property.

The prohibition applies in successive stages, starting with the most energy-intensive dwellings, and tightens over the years for the following classes. As the timetable has been changed several times, the only reliable method is to check the rule in force for the year in question rather than relying on a remembered deadline.

Two practical consequences for a landlord. First, a diagnostic close to the limit of a class deserves a cross-check before any commitment, since a tipping point changes the status of the property. Second, a diagnostic drawn up under an earlier calculation method can give a different rating from a diagnostic redone today: the date of completion matters as much as the result. This topic is covered in more detail in our article on the standards applicable to the performance diagnostic.

What is at stake in the case of an incomplete file

The absence of a mandatory diagnostic is not sanctioned by a simple fine. It deprives the seller of the benefit of the clause exempting them from liability for hidden defects for the disorder concerned. In concrete terms, a buyer who later discovers a defect covered by a missing diagnostic can request a price reduction, or even the cancellation of the sale.

An expired diagnostic produces the same effect as a missing diagnostic. This is why documents with short validity periods — the risk disclosure statement and termite report, six months — must be monitored between the signing of the preliminary sale agreement and that of the final deed, a period that frequently exceeds this threshold.

Finally, the diagnostic must be carried out by a certified and insured professional. A file compiled by an uncertified professional is unenforceable, regardless of the quality of its content.

Usage scenarios

Sale of an apartment in a co-owned building built before 1949. The file combines the Carrez measurement, the lead assessment, the asbestos report, the risk disclosure statement and, depending on the age of the installations, gas and electricity reports. This is the most comprehensive configuration.

Letting of a house from the 1980s. Asbestos and lead are out of scope. Attention focuses on the energy rating, which conditions the right to let the property, and on the installations if they are more than fifteen years old.

Managing a rental portfolio. Monitoring becomes a scheduling issue more than a one-off compliance matter: each property carries its own deadlines. Guidance on organising this monitoring is available in our rental management guide, and the traceability of document handovers ties in with that of the inventory of fixtures.

Frequently asked questions

How long does a diagnostic remain valid? This varies from six months — risk disclosure statement, termites — to ten years for the energy performance diagnostic, with unlimited durations for a negative asbestos or lead finding. The same service can have two different validity periods depending on whether it is used for a sale or a lease.

Can a sale diagnostic be used for a lease? Not systematically. Validity periods differ, and the measurement is not the same — Carrez area for co-owned properties in a sale, habitable area within the meaning of the loi Boutin for a lease.

What happens if a diagnostic is missing from the deed? The seller loses the benefit of the clause exempting them from liability for hidden defects for the disorder concerned. The buyer can request a price reduction or the cancellation of the sale.

Who can carry out these diagnostics? A diagnostician certified by an accredited body, holding professional liability insurance. A file drawn up by an uncertified professional is unenforceable.

Can the energy rating prevent letting? Yes. The most energy-intensive dwellings are progressively excluded from the rental market, in stages covering successive classes. As the timetable has changed several times, it must be checked for the current year.

Do diagnostics need to be redone after renovation work? Work affecting the floor area invalidates the measurement. Work relating to insulation or heating warrants a new performance diagnostic, which can change the property's class — in either direction.

Key takeaways

The list of mandatory diagnostics is built property by property, based on three parameters: the nature of the transaction, the age of the building and its installations, and the location. No standard checklist exempts you from this verification.

The real operational risk is not the omission of a diagnostic, which is visible, but the expiry of a document with a short validity period between the preliminary agreement and the deed. And the real strategic risk lies in the energy rating, which has become a condition for operating the property rather than mere information. These two points deserve to be tracked by deadline, not at the moment of signing.