Installing solar panels on existing buildings is often more complicated than it appears. Conventional systems add weight to roofs, require mounting structures and involve several installation steps. Supported by the Innovation Fund, the HELEXIO Line project is changing this approach with Helioroof®, an integrated roofing panel that combines insulation, weather protection and solar electricity generation in a single product.
When the roof becomes the solar panel
Across Europe, many industrial and commercial buildings are not suitable for conventional rooftop solar systems. Many roofs are not strong enough to support the extra weight of solar panels, and installation usually requires several different contractors working one after another. Project coordinator ArcelorMittal Building Solutions set out to overcome this challenge by bringing together roofing construction and photovoltaic manufacturing, two industries with very different approaches. After five years of research and development, and with 15 patents secured, the team created a lightweight integrated roofing system that generates electricity while providing all the functions of a standard insulated roof.
The new solution Helioroof ® is around 50% lighter than conventional solar roofs, with no exposed roof-level cabling and high electricity generation performance.
From innovation to industrial production
Turning the concept into an industrial product required designing an entirely new manufacturing process. Roofing and solar technologies follow different industrial logics and combining them required a highly automated and controlled production environment.
With support from the Innovation Fund, the project moved from pilot-scale development to a fully automated production line in Contrisson, France, inaugurated in October 2025. The facility now delivers an annual production capacity of 200 000 square metres of integrated solar roofing.
In 2024, Helioroof® received the Smarter E Award in the photovoltaics category at Intersolar, a leading international solar industry trade fair, recognising the innovation of the technology in building-integrated solar solutions. The first commercial installations are already in place, including an urban brewery in Liège, industrial buildings in Haut-Rhin and Meuse regions and a low-energy family home in the Marne region.
Behind the project is a multidisciplinary team of around 50 people working across research and development, manufacturing, production, sustainability and commercial activities. The goal is to make rooftop solar a standard part of building construction rather than an additional layer added afterwards.
Making solar roofs easier to install and safer to use
HELEXIO Line also introduces a new installation model. Roofers install the integrated panels using the same tools and techniques as conventional steel roofing. Electricians complete all electrical connections from inside the building, without needing to access the roof. This division of tasks improves safety and reduces installation time by around 40%.
The system is particularly suitable for renovation projects, where existing roofs may not support conventional solar installations. By reducing weight and simplifying installation, it opens new opportunities for buildings that were previously difficult to solarise.
Looking ahead, the project plans to expand production capacity and is considering a second manufacturing line to serve additional European markets. Training programmes for roofers and electricians are also being developed to support wider deployment.
Supporting Europe’s clean transition
As production increases, the HELEXIO Line plant workforce is expected to grow from around 20 people today to nearly 50, while the 15-person Helioroof® product team is set to expand with 30 further roles
The climate benefits are significant. During the first ten years of operation, the electricity generated by the integrated solar roofing technology is expected to avoid at least 170 000 tonnes of CO₂ emissions across Europe. This is broadly equivalent to the emissions produced by around 13 000 new passenger cars over the same period, based on average EU car emissions and annual mileage¹.
Each installation also reduces the roof’s carbon footprint by around 25% compared to conventional insulated steel roofs. The panels use XCarb®, a recycled and renewably produced steel, contain no hazardous chemicals and are designed to be 95% recoverable or recyclable at their end of life.
By integrating renewable electricity generation directly into building materials, HELEXIO Line shows how innovation can make clean energy easier to deploy, safer to install and more accessible for Europe’s buildings.
"Helioroof® is set to become a new standard for energy-efficient building renovations, with success above all being a collective achievement, driven by our committed network of partners."
Renaud Vignal, Head of Helioroof®
Learn more about the Innovation Fund.
[1] CO2 emissions performance of new passenger cars in Europe | Indicators | European Environment Agency (EEA)
Article published on 14 September 2026