RE2020 is the French environmental regulation for new buildings. Mandatory since 2022, it governs the energy performance and carbon footprint of buildings to be constructed. It does not govern the renovation of an existing house.
In renovation, other requirements apply. They depend on the equipment being replaced, the elements being renovated and local planning rules. Before starting work, it is therefore better to identify the framework that genuinely fits your situation, rather than reasoning from texts written for new build.
An effective energy renovation starts by identifying where heat is lost: roof, walls, floors, windows and doors, and thermal bridges. It is this overall assessment that lets you rank the works by impact, not the other way round.
Insulation, ventilation and heating have to be considered together. Insulating without dealing with ventilation can create damp problems; replacing the heating system without insulating amounts to heating your losses. French public grants are also available (MaPrimeRénov', the éco-PTZ interest-free loan, the CEE energy-saving certificates): check the schemes in force before starting the work.
Altering a façade, a roof or openings may require planning consent, even where the work is intended to improve energy performance. In Narbonne as in neighbouring communes, the PLU may impose constraints on appearance, particularly in protected areas. A visit to your commune's planning department before work starts avoids unpleasant surprises.
MCI Construction works in Narbonne and the Grand Narbonne, the Corbières, the Minervois and the Aude coast, as far as Béziers. The company will assess your renovation works and draw up a free quote, without replacing the regulatory surveys or assessments that remain necessary in some cases.