External wall insulation in Aix-les-Bains.

External wall insulation, or ITE, involves wrapping all the walls of your house in a continuous insulating layer, fixed to the outer face of the façade and then covered with render or cladding. The building is thus protected from both cold and heat from the outside, like a coat pulled on over the existing structure.

The key difference from internal wall insulation (ITI) lies in the principle: external insulation does not encroach on living space. You do not lose a single square metre inside, you do not have to move your furniture and you can stay in your home during the works. Above all, external insulation effectively eliminates thermal bridges — those areas where heat escapes at floors, corners and internal walls — which internal insulation deals with far less well.

In the Savoie climate, with cold winters around Lake Bourget and on the heights of the Revard, this continuous treatment of the building envelope transforms comfort. The walls stay warm, the thermal mass of the building is preserved and heating bills fall for good. It is now one of the most effective and best-subsidised energy renovation solutions for a detached house in Aix-les-Bains.

There are several ways of installing external insulation, and the choice depends on the architecture of your façade, the look you want and your budget. The most common technique is rendered external insulation: insulation boards (polystyrene, mineral wool or wood fibre) are bonded and mechanically fixed to the wall, then covered with a mesh-reinforced base coat and a finishing render. The result looks like a conventional rendered façade, in the colour of your choice.

Clad external insulation, on the other hand, relies on a framework fixed to the façade, which holds the insulation and then a ventilated facing: timber cladding, composite cladding, metal or mineral materials. This solution provides a very durable ventilated air gap, a wide choice of looks and blends perfectly with the mountain identity of Savoyard chalets and houses. Finally, insulated facing panels and ready-to-fit insulation boards allow fast installation in certain configurations.

The right choice is made case by case: a very flat, regular façade lends itself well to render; a façade you want to clad in timber, or one that is uneven, will be better served by cladding. We study the insulation thickness required, the treatment of detailing (window sills, roof overhangs, downpipes) and local plan (PLU) constraints before recommending the most suitable technique.

One of the great advantages of external insulation is that it combines naturally with façade restoration. If your façade is looking tired — cracked render, dirt, flaking paint — and restoration is needed anyway, it is the ideal time to insulate. Rather than simply freshening up an uninsulated wall, you share the cost of scaffolding and labour to carry out two projects in one.

The benefit is twofold: you improve energy performance while giving your home a complete aesthetic makeover. New render colours, contemporary timber cladding, redesigned mouldings: external insulation is an opportunity to modernise the look of your property and increase its value. For a co-ownership building or a house in the centre of Aix-les-Bains, it is also an opportunity to harmonise the whole façade.

Atelier NovAlp coordinates the entire operation: survey of the existing building, choice of materials, submission of the prior declaration (déclaration préalable) of works, façade treatment if needed, fitting the insulation and finishing. You have a single point of contact from design through to handover.

External wall insulation is among the best-supported measures under public schemes. As an RGE CertiRénov-certified company (no. CR-2026-73-0095), Atelier NovAlp enables you to use MaPrimeRénov', Energy Savings Certificates (CEE) and the zero-interest eco-loan to finance your external insulation. These grants, which can be combined subject to conditions, greatly reduce your out-of-pocket cost and make the project affordable.

In terms of performance, walls account for up to 25% of heat loss in a poorly insulated house. By treating this surface continuously, external insulation delivers immediate heating savings and improves the home's energy rating (DPE) — a decisive advantage when selling or letting. Summer comfort also improves, as the walls act as a shield against the heat.

To go further, external insulation fits perfectly into a comprehensive energy renovation in Aix-les-Bains: combined with loft insulation, replacement windows and doors and a heat pump, it can deliver spectacular savings. Find out more about our approach and our guarantees on our RGE energy renovation page.