ArcelorMittal showcases XCarb^® recycled and renewably produced steel as new headquarters building takes shape

15 October 2025

The construction of ArcelorMittal’s new headquarters in Luxembourg is gathering pace, with the building emerging onto the skyline of the capital’s Kirchberg business district. At present, the construction site is the largest in Luxembourg and the Greater Region (Saar-Lorraine-Luxembourg-Belgium).

XCarb^® recycled and renewably produced steel is the flagship product used in the building’s exoskeleton, and is the latest addition to ArcelorMittal’s long products range. It represents the achievement of more than a century of steelmaking innovation in Luxembourg and stands as a testament to the company’s commitment to a future of net-zero steel. As ArcelorMittal’s most advanced solution in terms of low carbon-emissions steel, XCarb^® recycled and renewably produced steel embodies both technological progress and environmental responsibility.

A flagship of sustainable construction

ArcelorMittal announced in June 2023 that the first beam in the 21-storey building had been installed, with the building intended to serve as a showcase for the unique role that steel can play in sustainable construction.

Now standing at more than eight storeys high (the stairwells surpass the eighth floor, while the steel frame and floor decks reach the sixth floor), the building is scheduled to be ready for use by ArcelorMittal employees in 2027.

Since the outset of the project, the sustainability of the building, together with the quality of the working environment for employees, has been the priority. The building serves as a showcase for Steligence^®, ArcelorMittal’s proprietary design philosophy, which combines sustainability, innovation and flexibility in construction at scale, and covers steel, glass and green spaces.

The building’s key environmental credentials include the following:

• The exoskeleton is being built with XCarb^® recycled and renewably produced steel, which is made in Luxembourg with 100% recycled steel in an electric arc furnace that uses 100% renewable energy. Each steel beam used in the building has a carbon footprint of 333kg per tonne – a saving of 10.4t of carbon dioxide (CO₂) per beam. In total, the building will contain more than 14,000t of steel, 95% of which is XCarb^® recycled and renewably produced steel. The XCarb^® recycled and renewably produced steel is produced in Differdange and Belval and fabricated in the Steligence^® fabrication centre.
• Steel constructions are seven to 10 times lighter than traditional reinforced concrete buildings, and so save the production and the transport of a large amount of material, which significantly reduces the carbon footprint.
• The construction techniques used for the building will make it energy efficient and low-carbon, and have been certified “BREEAM exceptional”, “DGNB gold” and “WELL gold”. BREEAM (the Building Research Establishment environmental assessment method) focuses on the environmental performance and resource use efficiency; DGNB (the German Sustainable Building Council) takes a comprehensive approach that integrates economic, ecological and socio-cultural criteria; and Well (a building control system from the International Well Building Institute) assesses the health, comfort and wellbeing of a building’s occupants.

A unique building that harnesses the full architectural potential of steel

The project was the subject of an international architectural competition in 2017, which was won by Wilmotte & Associés from Paris. The brief was to design “a contemporary and sustainable building that exploits the full potential of steel from top to bottom”. The result is a truly unique building, including cutting-edge products and features resulting from close collaboration between the architect and ArcelorMittal’s research and development teams. The architect defined four major conceptual themes for the project:

• A monolithic, structural glazed façade with an open-air section and rooftop with planted terraces and covered in photovoltaic panels.
• An atrium with aerial footbridges.
• Four-structural elements building that highlights the use of steel.
• Office floors 20m wide and free of intermediate columns, to create an ultra-flexible building. The column-free spans are made possible by the intelligent combination of high-strength steel cellular beams and a composite floor.

The headquarters will bring together staff from ArcelorMittal’s current headquarters; Aperam employees will also be present in this building.

In their own words: reflections on the new headquarters

From left: Jean-Marc Wilmotte, Olivier Vassart, Vijay Goyal, and Pierre Engel at an event showcasing the building’s progress on 26 September © Raoul Gilibert

Vijay Goyal, executive vice president of ArcelorMittal, whose responsibilities include the headquarters project:

“ArcelorMittal’s own path is inseparable from Luxembourg’s steel heritage. From ARBED’s leadership in Luxembourg, through the creation of Arcelor, and ultimately to the company’s evolution as ArcelorMittal, the world’s leading steel and mining company, Luxembourg has remained not only our home but also our symbol of resilience, transformation and ambition. It is with that spirit that we envisioned headquarters that reflect who we are today and what we aspire to become tomorrow. We chose Kirchberg because it represents Luxembourg’s modern face: a vibrant international business district at the very heart of Europe. Our new flagship headquarters will serve as a visible beacon of our vision.”

Jean-Michel Wilmotte:

“This building, made from the DNA of ArcelorMittal, is hatching and blooming towards the sky in the Kirchberg district.”

Pierre Engel, chief engineer, ArcelorMittal, and head of ArcelorMittal’s headquarters construction project:

“In terms of steel and glass architecture, the materials available today are materials that Ludwig Mies van der Rohe, a Bauhaus master, would have dreamed of. They include our much-admired low-carbon-emissions steel, generating long spans and slender columns, but also amazing glass, which brings natural light and exceptional insulation to the building.”

Olivier Vassart, chief executive officer, Steligence^®:

“This building is more than our future headquarters – it’s a living demonstration of what steel can achieve in sustainable construction. By using XCarb^®, we’re not only reducing the carbon footprint of our headquarters, but also setting a new benchmark for innovation, resilience and environmental responsibility in the built environment.”