engineering free-form glass façades

Complex free-form façades can be realised economically when they are planned digitally at an early stage and developed in an integrated manner. Precise 3D models enable optimal coordination between geometry, structural design and fabrication, thereby reducing the need for costly adjustments in later project phases. A key component of this 3D expertise is the targeted use of automation, particularly in design, data processing and production. The ability to apply automated bending processes has further improved fabrication efficiency while ensuring a high level of repeat accuracy throughout the entire lifecycle.

Maximum transparency in large-format glass façades is achieved through the consistent separation of load paths and the targeted use of delicate supporting structures. Vertical loads are transferred via slender tension rods, while horizontal forces are introduced into the system almost invisibly using structural silicone. In combination with large-format, curved glass, this creates highly transparent façades in which the structure remains structurally effective but recedes visually into the background.

In non-linear geometries, loads are transferred via a holistically coordinated structural system. The curvature of the glass surfaces increases the inherent stiffness and promotes uniform load distribution, while tension members, fins and substructures specifically transfer dead weight and wind loads into the primary structure. Temperature-induced deformations and constraints are analysed and structurally accounted for as early as the initial planning phase.

The limits are primarily defined by curvature radii, glass dimensions and manufacturing constraints. With radii below 500 mm and panel sizes of up to 11.5 × 3.6 × 1.2 m, the possibilities are already considerable. The minimum achievable radius depends on glass thickness and geometry. 3D-curved panes can be further processed without restriction into laminated safety glass, insulating glass units and complex façade elements.

The impact on the budget and construction schedule depends largely on the extent of technical planning carried out early in the process. Free-form façades require greater effort during the design and engineering phases, but they enable a high degree of cost transparency through parametric modeling, systemic optimisation, and manufacturing and installation concepts coordinated at an early stage. If geometry, structural framework, glass and steel fabrication, and the installation sequence are planned in an integrated manner, free forms can be implemented cost-effectively.

Parametric 3D models form the basis for this. Geometry, load assumptions, tolerances and assembly conditions are consistently represented and verified within these models. It is crucial that the design concept is not viewed in isolation, but is continuously validated structurally, developed constructively and aligned with the actual capabilities of glass and steel fabrication. Mock-ups, test structures and digital simulations serve to verify critical details. Close collaboration across all disciplines – architecture, façade engineering, structural engineering, fabrication and installation – ensures that the designed geometry is not only aesthetically compelling but also technically well-defined, reproducible and realisable under controlled conditions.

When creating free-form glass façades, seele primarily rely on machine-based glass bending processes to produce both tempered (ESG) and heat-strengthened (TVG) glazing. Bending technologies and CNC-supported finishing in the field of architectural steel construction are also crucial. With a fully integrated digital planning approach (CAD/BIM), workshop drawings can be transferred directly to production machinery. In addition, custom-designed substructure and fixing systems are required to meet the geometric, structural, and building physics requirements.

In free-form glass façades, functional elements such as opening units, shading and maintenance access are incorporated at an early stage within the digital geometry development. Openings are either geometrically segmented or positioned in zones with reduced curvature to enable the use of technically feasible hardware and sealing systems. Shading systems are designed either as integral façade components (e.g. louvered or printed glass elements) or as supplementary systems adapted to the geometry. Maintenance and cleaning considerations are addressed through walkable structures, defined access points or reversible façade elements. The objective is to achieve seamless functional integration without compromising the overall geometry.