That file must obligatorily be appended to any promise to sell and to any sale of a dwelling, and must be supplied by the landlord to the tenant of any premises used for housing or for combined housing and business use. It must be drawn up by a professional whose skills have been certified by an approved body and who has taken out insurance covering his or her liability. With concern to protect the consumer, the DDT gives an assessment on the presence of materials or products containing asbestos, on the risk of exposure to lead, on the presence of termites, on natural and technological risks, on energy performance, and, a recent addition, on interior gas installations. Inspecting the interior electrical installations will be mandatory a few months from now, as will inspection of non-collective sewage installations (sceptic tanks and the like) when the dwelling is not connected up to the mains sewer. The cost of establishing the technical diagnostic file falls to the vendor. If you are putting a property on the market, do not hesitate to consult several professionals so as to compare their prices, while also checking that they satisfy the certification, insurance, and independence conditions provided for by Law. The technician should show you evidence of satisfying those conditions by giving you a certificate. Diagnostic surveys established prior to November 1, 2007 by a non-certified operator may be used until their period of validity expires, that period normally appearing on the survey. Similarly, when interior gas installations that are over fifteen years old have been altered or supplemented, and have been the subject of a certificate of compliance issued by an approved body and dated less than three years before the date of the officially recorded deed of sale, no new certification document is required. If you are the vendor, do not hesitate to ask your notary to inform you of your exact obligations. The Law requires you to supply those documents on pain of being held liable for the consequences of such lack of information of the acquirer, and possibly of other people who might suffer harm (occupant, tenant, etc.). Moreover, the information contained in some of those documents is of interest for public health, which cannot exempt you from having to produce them or discharge you from your liability. If you are the buyer, it is in your very best interest to inform yourself as broadly as possible so to make no mistake about the characteristics of the property that you are thinking of buying. Those diagnostic surveys give the buyer a more precise idea about his or her investment, and about its advantages and its disadvantages. It is possible that, in the future, other checks and inspections might be added to the file, with the continued aim of giving improved information and improved protection, and of avoiding disputes between vendors and acquirers due to nasty surprises. Your notary will then be there to inform you. December 2007