Mandatory Property Diagnostic: Complete List 2026

The sale of a property in France requires the seller to provide the buyer with a Technical Diagnostic Report (DDT) appended to the promise of sale or the authentic deed. In 2026, regulations are tightening, particularly on energy efficiency with the progressive ban on renting out energy-inefficient properties. Mastering the exhaustive list of mandatory diagnostics is therefore essential to legally secure the transaction and avoid post-sale disputes. This article provides a comprehensive overview of the diagnostics required in 2026 based on the nature of the property, its location and year of construction.

Legal Framework of the Technical Diagnostic Report

The DDT is governed by articles L.271-4 to L.271-6 of the Construction and Housing Code (CCH). Its absence engages the seller's liability and may result in cancellation of the sale, price reduction, or action under the warranty of hidden defects. Each diagnostic must be carried out by a COFRAC-certified diagnostician, in accordance with decree no. 2006-1114. The validity period varies depending on the type of diagnostic, and an expired document cannot be relied upon against the buyer.

List of 10 Mandatory Diagnostics in 2026

1. Energy Performance Certificate (EPC) — Mandatory for all residential properties, valid for 10 years. Since 2025, properties rated G are banned from rental; F will be banned in 2028.

1. Asbestos Diagnostic — Mandatory for properties with a building permit issued before 1 July 1997. Unlimited validity if no asbestos detected.

1. Lead Risk Exposure Report (CREP) — For properties built before 1 January 1949. Validity of 1 year if positive, unlimited if negative.

1. Report on Risk of Termite Infestation — Mandatory in zones defined by prefectural order. Validity 6 months.

1. Report on Interior Gas Installation — For installations over 15 years old. Validity 3 years.

1. Report on Interior Electrical Installation — For installations over 15 years old. Validity 3 years.

1. Report on Risks and Pollution (ERP) — Mandatory in areas covered by a hazard prevention plan (natural, mining, technological), seismic risk, radon. Validity 6 months.

1. Non-mains Sewerage System Diagnostic — For properties not connected to mains sewerage. Validity 3 years.

1. Carrez Law Measurement — For all co-owned units (excluding cellars, garages, terraces). Unlimited duration unless there are alterations.

1. Energy Audit — Mandatory since 1 April 2023 for the sale of properties rated F or G, extended to class E in 2025 and class D in 2034.

Penalties and Liability for Non-Compliance

The absence of a mandatory diagnostic deprives the seller of the clause exempting from warranty of hidden defects (article 1641 of the Civil Code). An incorrect EPC can now engage the liability of both the diagnostician AND the seller, following its binding nature established by the Climate and Resilience Act of 22 August 2021. Criminal penalties can reach €37,500 in fines for false declaration concerning asbestos or lead.