Your roof insulation expert
Isoleaz assists you with your roof insulation in Luxembourg
Premium assistance
Our experts will assist you in obtaining grants for insulating your home.
Tailored support
We provide personalized support for each project before, during, and after the work.
Your insulation expert
Collaborating with Isoleaz guarantees quality work by certified experts.
Isoleaz, your roof insulation specialist in Luxembourg
At Isoleaz, we handle all types of roof insulation projects in Luxembourg. Our team of qualified professionals carefully analyzes each situation to offer you the best solution for your home, and supports you from the initial site visit to the final handover of the project.
Why is insulating your roof a priority?
The roof is one of the most thermally critical areas of a building. Without effective insulation, heat loss through the roof can account for up to 30% of a home’s total heat loss, making it the most impactful area of energy renovation that should be addressed as a priority. In summer, a poorly insulated roof allows outside heat to penetrate and overheats the attic spaces. In winter, the heat produced by the heating system escapes, forcing the equipment to run longer and consume more energy.
In Luxembourg, where summers are gradually getting hotter and winters remain harsh, insulating the building envelope is a particularly profitable long-term investment. The savings on heating and cooling bills can be substantial, and the improved Energy Performance Certificate (EPC) directly increases the property’s value on the real estate market.
Roof insulation can also be considered as part of a roof renovation. When tiles or slates reach the end of their life, combining the two interventions into a single project optimizes the budget and limits disruption for the occupants.
Do you want to insulate your home?
Ask our team of experts for advice
Roof insulation from the inside
Interior insulation is the most common technique, especially when the attic is converted or intended to be converted. It involves installing insulating materials between the rafters or trusses of the roof structure, from inside the dwelling. To enhance thermal performance and prevent condensation, a vapor barrier is always installed alongside the insulation layer.
This method offers several significant advantages:
- A generally more affordable cost than external insulation
- Faster installation, as all work is carried out entirely from the inside
- Adaptability to convertible attic spaces, making it possible to create additional living space while improving insulation
However, its limitations should be anticipated. Installing insulation between the rafters slightly reduces the ceiling height, and the affected rooms must be vacated for the duration of the work. Finishing work, such as painting or installing new wall coverings, will be necessary after the work is completed.
Exterior roof insulation
Exterior insulation involves removing the existing roof covering, such as tiles or slates, and installing the insulation directly onto the roof deck before replacing or renewing the covering. This is the most thermally efficient solution because it eliminates almost all thermal bridges by treating the building envelope continuously and without interruption.
This technique is particularly recommended in two situations: when the roof covering is in poor condition and needs to be replaced, or in the case of a flat roof, where interior insulation can promote condensation and lead to moisture problems.
Its main strengths are as follows:
- Occupants can remain in the property during the work, as all work is carried out externally.
- Ceiling height is fully preserved, with no loss of living space.
- The internal roof structure remains visible and can be highlighted for a warmer, more attractive finish.
- An opportunity to combine roof renovation and insulation into a single project, reducing the overall cost.
Its main drawback is its price, which is significantly higher than interior insulation. This is why it is most often carried out simultaneously with roof replacement, in order to share installation and labor costs.
What materials should I use to insulate my roof?
Choosing insulation is a crucial decision that depends on the chosen technique, the roof configuration, and the desired performance levels. Several types are available on the market.
Insulation generally comes in two main forms:
- In rigid or semi-rigid panels, integrated directly into the roof structure or laid on the roofing support
- Loose, blown or mechanically projected to uniformly fill available spaces, particularly in attics
Les isolants minéraux
La laine de verre et la laine de roche sont les matériaux les plus utilisés pour l'isolation de toiture, aussi bien par l'intérieur que par l'extérieur. Leurs performances thermiques et acoustiques sont reconnues, leur résistance au feu est élevée, et leur rapport qualité-prix reste compétitif.
La laine de roche se distingue par sa densité et sa capacité à conserver ses propriétés même en présence d'humidité, ce qui la rend particulièrement adaptée aux toitures exposées.
Les isolants synthétiques pour toiture-terrasse
Dans le cas d'une toiture-terrasse, certains matériaux sont spécifiquement adaptés aux contraintes de ce type de surface. Le polyuréthane, le verre cellulaire et la perlite expansée figurent parmi les solutions les plus performantes pour ce cas de figure.
Leur résistance à l'humidité et leur capacité portante en font des choix pertinents pour les toits plats ou à très faible pente.
Les isolants biosourcés
Pour les propriétaires souhaitant privilégier des matériaux à faible impact environnemental, plusieurs alternatives naturelles sont disponibles : la ouate de cellulose, les fibres de bois, le liège expansé ou encore le chanvre. Ces isolants offrent de bonnes performances thermiques et une régulation naturelle de l'humidité, tout en présentant un bilan carbone plus favorable que les matériaux synthétiques. Ils sont particulièrement adaptés aux projets de rénovation écologique ou aux bâtiments à ossature bois.
Nos conseillers Isoleaz vous guident dans le choix du matériau le mieux adapté à votre toiture, en tenant compte de la technique retenue, de votre budget et de vos priorités en matière de durabilité.
Do you want to insulate your home?
Ask our team of experts for advice
What budget should be planned for roof insulation in Luxembourg?
The cost of roof insulation varies depending on several factors: the technique chosen, the surface area to be treated, the material selected, the condition of the roof structure, and the constraints of site access.
In Luxembourg, the general level of tariffs in the construction sector is higher than in neighboring countries, which must be taken into account in the budget estimate.
Exterior insulation
Installation on the roof, without loss of living space
40 - 90
euros / m2
Excluding taxes
Interior insulation
Installation under sloping roofs, ideal for occasional renovations
70 - 180
euros / m2
Excluding taxes
Good to know : Interior insulation is generally less expensive to install, but exterior insulation, when carried out at the same time as roof renovation, often allows for some of the additional costs to be offset by combining the work.
Your personalized quote
At Isoleaz, we provide you with a complete and personalized quote within a maximum of 24 hours, giving you a clear overview of the budget before any commitment.
Financial aid for roof insulation in Luxembourg
Several public aid schemes are available in the Grand Duchy to finance roof insulation work and reduce the initial investment.
The Klimabonus Wunnen
Managed by the Klima-Agence, the Klimabonus Wunnen is Luxembourg’s main subsidy for the energy renovation of existing housing. It covers roof insulation work, provided that the thermal performance levels achieved meet the thresholds defined by the program. This scheme is available to both owner-occupiers and landlords, subject to conditions specified by the Klima-Agence.
The PRIMe House bonus
The PRIMe House grant provides additional financial support for energy efficiency improvements, including roof insulation. The grant amount depends on the type of work carried out, the performance results achieved, and the applicant’s profile. Applications are processed according to a set schedule, so it is advisable to begin the process well in advance of starting the work.
VAT reduced to 3%
Renovation work carried out on a Luxembourg property that is more than two years old benefits from a reduced VAT rate of 3%, compared to the standard rate of 17%. This reduction is applied without any special administrative procedures and represents an immediate and significant saving on the total bill.
Municipal aid
Some municipalities in the Grand Duchy offer additional local subsidies for roof insulation work. These subsidies vary from one municipality to another, both in form and amount. The myenergy portal makes it easy to identify the subsidies available in your municipality and is a useful starting point for preparing your application.