In Narbonne, insulation is not just about winter heating. Long, hot summers, the tramontane and strong sunshine make summer comfort at least as important as keeping winter bills down. Well-designed insulation works both ways: it holds the heat in during the cold season and keeps it out during the warm one.
Before starting work, it is worth identifying the weak points of the house: roof, walls, ground floors, windows and doors. The priorities differ with the age of the house, how it was built and how it is exposed.
External wall insulation means wrapping the façades in an insulating layer, covered with a render or cladding. Its great advantage: it deals with the thermal bridges at floor junctions and internal cross walls without reducing the living area, and it gives the façades a fresh look at the same time.
Several materials are commonly used: expanded polystyrene, rock wool, wood fibre or hemp, each with its own strengths in terms of performance, thermal mass and behaviour in the presence of moisture. In a region with hot summers, dense insulants, which slow the heat down, deserve particular attention.
One point to watch: changing the external appearance of a house may require a déclaration préalable, a prior notification of works lodged at the mairie, and some PLU zones impose constraints on façades. Checking beforehand avoids unpleasant surprises.
A large share of the heat lost from a poorly insulated house goes through the roof. That is often the most effective place to start.
The technique depends on the layout: blown loose-fill insulation in an unconverted loft, boards or rolls fitted between the rafters in a converted one, or sarking, insulation laid over the roof structure, where the roof covering has to be redone in any case. That last option deals with insulation and roof in a single operation.
In every case, ventilation must be rethought at the same time as insulation: a house made more airtight without controlled air renewal is exposed to condensation and the problems that come with it.
Old windows let heat out in winter and let it in during summer. Moving to high-performance double glazing, with airtight frames, noticeably improves thermal comfort, and often acoustic comfort too.
In the Aude climate, solar shading counts as much as the glazing itself: shutters, external blinds or roof overhangs limit summer overheating on façades facing south and west.
French energy renovation grants exist (MaPrimeRénov', the éco-prêt à taux zéro interest-free loan, the CEE energy-saving certificates). Their conditions change regularly: check the rules in force in France before signing a quote. Note too that RE2020 governs new build; in renovation, other requirements apply to work on an existing house.
MCI Construction works in Narbonne, the Grand Narbonne, the Corbières, the Minervois and along the Aude coast, as far as Béziers. The company will assess your project, advise you on the order of the works and draw up a free quote.