Back to work Category: Technics & design, Facades Würzburg, Hubland

Bezirk Unterfranken Construction of a New Administrative Building

The new construction comprises an office building with associated ancillary spaces, as well as an underground parking garage for the future occupant, the District of Lower Franconia. The building is located in the “Skyline Hill” industrial park in Würzburg. Spread across five full stories, the building will feature modern, forward-looking workspaces that enable flexible and dynamic work.

The building was constructed with the goal of achieving maximum energy efficiency and self-sufficiency. A connection to the district heating network is not necessary, as the property—as a pilot project—can be operated largely self-sufficiently. A photovoltaic system with a capacity of approximately 60 kWp covers the building’s electricity needs and powers a heat pump that handles both heating and cooling.

For this project, we realized a multi-part, individually engineered facade system with a load-bearing substructure made of hot-dip galvanized steel. Differently dimensioned brackets (t=3.0–5.0 mm) transfer, floor by floor, both the dead loads of the window elements and the metal facade as well as the wind loads and the loads from the column cladding — despite varying substrates of timber and concrete. The vertical and horizontal substructure, made of zinc-magnesium-coated sheet steel, forms the precise bearing surface for the window sill, parapet coping, and blind box.

The floor-by-floor continuous window sill in aluminum (t=1.0 mm, color "Medium Bronze B40", Kalzip) consists of individually cut components with varying depths, avoiding thermal bridging in front of the column cladding while structurally accommodating temperature-related linear expansion. Overlapping joints with sliding covers secure the connections against penetrating rainwater.

The suspended meander facade in front of the concrete parapet and slab edge (aluminum t=1.0 mm, color "Ultra Dark", Kalzip) impresses with its distinctive relief: five specially developed profile cross-sections with varying corrugation widths enable an optimized cutting layout, differing installation directions, and a consistently harmonious corrugation pattern. The unconnected individual elements — interlocked at the joints, riveted at the lower edge, and fitted with slotted holes for vertical expansion — absorb horizontal thermal expansion without stress.

The staircase shading is achieved through extruded aluminum rectangular tubes in three cross-sections, anodized in E6C32 to match the surrounding facade trim. The degree of openness decreases with increasing floor height, controlled by the growing proportion of larger tube cross-sections — a design concept as thoughtful in appearance as it is in function.