DTG: building condition survey in a French co-ownership

What the DTG contains

Article L731-1 of the Construction and Housing Code and service-public.gouv.fr (F32059) set out its content:

• an analysis of the apparent condition of the common parts and common equipment;
• the condition of the building with regard to legal and regulatory obligations relating to construction;
• an analysis of possible improvements in technical and asset management;
• a diagnostic de performance énergétique (energy performance certificate) for the building;
• a rough cost estimate and a list of the works needed to preserve the building, protect occupants’ health and safety and save energy, specifying those to be carried out in the next ten years.

The DTG is entrusted to a professional with proven skills in construction methods, technical equipment and materials, through a degree, qualification or certification. They attest on their honour to their impartiality with regard to the syndic (building manager), energy suppliers and contractors working on the building, and hold professional liability insurance (F32059). Service-public.gouv.fr cites an engineering consultancy, an architect or a thermal engineer.

When is the DTG compulsory?

Division into co-ownership. The obligation is assessed at the date of the division: a building constructed in 2014 and divided into co-ownership in 2025 must have a DTG (F32059).

Existing co-ownerships. Carrying it out is not itself required, but the question must be put to the assemblée générale (owners’ general meeting), which decides on the principle and the terms by a majority of the votes cast (article 24). Once carried out, the DTG is presented at the first general meeting following its completion or revision (art. L731-2); the co-owners then decide what action to take on its recommendations (F32059).

Run-down buildings. The mayor or prefect may request the DTG where the building poses a danger to the health of occupants or neighbours, a lack of maintenance seriously compromising its use as housing, or a risk of collapse (F32059).

Cost, payment and access

There is no regulated fee: the price depends on the number of lots, the architecture, the structure and the location of the building. The cost is shared among all co-owners according to their tantièmes (shares) and is not recoverable from the tenant (F32059). It can be financed from the fonds de travaux (works fund), which covers drawing up the draft multi-year plan and, where applicable, the DTG (F34026). See also our guide on charges de copropriété (service charges).

The DTG is included in the building’s carnet d’entretien (maintenance log), which the syndic must make available online, downloadable and printable (F32059).

DTG and draft multi-year works plan: how they fit together

Since 1 January 2025, a draft multi-year works plan (PPPT) is in principle compulsory, in mainland France, in all buildings intended wholly or partly for residential use that are more than 15 years old, whatever the number of lots (F36760; ANIL). In the overseas départements and regions, the obligation applies from 1 January 2028 (ANIL). The two documents are similar but do not serve the same purpose:

Sources: CCH, art. L731-1 and L731-4; 1965 Act, art. 14-2; service-public.gouv.fr (F32059, F36760).

The DTG feeds into the draft. The draft PPT is drawn up on the basis of an analysis of the structure and equipment, the energy performance certificate and, if one has been carried out, the DTG (art. 14-2; F36760).

The exemption. If the DTG shows no need for works in the ten years following its preparation, the syndicat (owners’ association) is exempt from drawing up the draft PPT (art. 14-2), for as long as the survey remains valid (ANIL). For voting rules and grants, see our guide on rénovation en copropriété (renovation in a co-ownership).

On the sale of a lot

The conclusions of the DTG, if there is one, are among the documents handed to the buyer with the promesse de vente (preliminary sale contract), together with the adopted multi-year plan or its draft (F37190). A recent DTG costing major works in the short term weighs on the lot’s future charges: see our guide acheter en copropriété (buying in a co-ownership).

Which professional to consult

If you are buying a lot, the agent immobilier (estate agent) and the notaire (notary) give you the conclusions of the DTG and the multi-year plan with the preliminary contract. The diagnostiqueur (property surveyor), for their part, prepares the survey file for the private part, to be read alongside the conclusions of the DTG.