The exterior wall is a steel frame with double-shell infill. The exterior wall is flush with the steel structure, constructed of half-brick-thick masonry with mortar joints. The interior wall is finished with 2 cm of lime plaster. The joint to the steel is sealed with permanently elastic sealant. A 4 cm air gap between the two shells allows for air circulation. The inner shell consists of 5 cm thick aerated concrete panels with a white slurry finish. Expansion joints are accommodated by embedded strips of foam insulation, which also serve to eliminate thermal bridging. The wall complies with DIN 4102 and is therefore fire-resistant.






