The compact, four-storey office building without cellar has a north-south orientation. The staircase protrudes on the north side of the building. This is where the sanitary facilities can be found on each floor. The large-surfaced floor plan without load-bearing interior walls allows a flexible subdivision. The depth of the building of 16 m makes it possible for adjoining rooms to be accommodated in the central zone. Five parties currently use the building with approx. 100 workplaces in total. In theory, up to eight units would be possible per floor.
The reinforced concrete skeleton construction with load-bearing precast concrete facades was, for the most part, prefabricated. The building shell was therefore finished within 8 weeks and the whole building within 9 months. The high standard of insulation is in line with the construction method of a passive house but only reaches an average U-value of 0.48 W/m²K. This is, among other things, a result of the glazing in the slightly-heated staircase which, however, is located inside the insulated envelope, with a U-value of 1.6 W/m²K. The outer walls are insulated with 20 cm mineral wool and faced with square tiles ventilated at rear. The windows in the office zones consist of triple glazing in thermically separated aluminium frames (UW=0.80 W/m²K). The windows account for 41% of the facade surface area. Because of the glazing’s comparatively low g-value of approx. 50% and cooling using concrete core temperature control, exterior shading was not installed.
With an annual heating requirement calculated at 39 kWh/m² p.a., the office building falls below the then permitted value of the Heat Conservation Ordinance 95 (WSVO) by almost 40%. The air-tightness test of the building envelope produced an n50-value of 0.3 h-1.