Laser Welded Curtain Wall Profiles for the Hahn+Kolb Headquarters in Ludwigsburg
The headquarters of HAHN+KOLB in Ludwigsburg, Germany, is a large-scale building complex designed by SHA (Sigrid Hintersteininger Architects) covering 48,000 square metres. The facility combines sales offices, a technological centre, and a logistics centre with 540,000 storage bins reaching up to 16 metres in height. The curtain wall system enclosing the complex required custom mullions and transoms that could integrate high-performance green technologies for heating, cooling, and solar energy production, while remaining visually invisible from the exterior. SHA specified tailor-made laser welded mild steel profiles from Montanstahl to meet these requirements.
Mullions Designed to Disappear Behind the Glass
The curtain wall specification called for mullions and transoms in two distinct cross-section geometries: T-sections and angle bars, both in custom non-standard lengths. A key design requirement was that the flange width of each profile had to fall within the junction width of the glass panels, making the structural members invisible from the building exterior. This constraint drove the cross-section geometry: profiles could not simply be selected from a standard catalogue but had to be sized precisely to the glazing system. The brief also required the curtain wall to integrate technologies for active heating and cooling and photovoltaic energy production, adding functional complexity to what was already an architecturally demanding specification.
Laser Welded from Plate, Mitre Cut, and Sandblasted for Site Assembly
Montanstahl produced the mullion and transom profiles by cutting flat strips from mild steel plate and joining them by laser welding to form the specified T-section and angle bar geometries. The laser welding process allowed precise control over flange and web dimensions, ensuring the finished profiles met the tight fit-within-glass-junction requirement. Profiles were supplied in custom lengths and mitre cut to simplify on-site assembly. Sandblasting was applied across all sections to achieve the required surface quality, and a protective paint coating was applied to ensure long-term corrosion resistance on the exposed building envelope.
Application Context
This project is part of Montanstahl’s architecture, building and construction segment, where laser welded special profiles are specified for curtain wall systems, facades, and structurally glazed envelopes requiring custom cross-section geometries. When standard catalogue sections cannot meet the dimensional constraints of the glazing system or the aesthetic intent of the design, laser welding from plate allows any T, angle, or compound section to be produced to the exact geometry required. Montanstahl supplies curtain wall profiles of this type for architectural projects across Europe and worldwide.