Roof insulation prices in Luxembourg

2 - Total area to be treated

The price is generally expressed per square meter. A large area implies a higher quantity of materials and a longer intervention time, which increases the overall budget.

3 - The chosen insulation technique

The chosen method has a direct impact on the final amount. Several options are possible:

• external insulation (sarking),
• internal insulation under slopes
• insulation of the floor of lost attics.

External insulation often requires a complete roof refurbishment, making it more expensive.

Internal insulation involves placing the insulation between or under the rafters.

Insulating the floor of lost attics generally remains the most economical alternative.

4 - The selected insulating material

Different products can be used to insulate a roof:

• rock wool,
• cellulose wadding,
• glass wool,
• polystyrene panels,
• wood fiber,
• polyurethane foam.

In Luxembourg, the average price ranges are as follows:

• Cellulose wadding or rock wool: 30 € to 55 €/m²
• Glass wool or polystyrene: 20 € to 35 €/m²

Each solution has its own performance in terms of thermal and acoustic insulation.

5 - The thickness of the insulating layer

A greater thickness improves thermal resistance but requires a larger volume of material. This increase in quantity logically leads to a rise in the overall cost.

6 - Preliminary work and finishes

The budget may change if preparatory work is necessary before installing the insulation, for example:

• thorough cleaning of the roof,
• removal of existing elements,
• repair or reinforcement of the framework,
• installation of a waterproofing screen,
• finishes around roof openings.

These operations influence both the cost of materials and that of labor.