20er Haus Art Museum , Vienna (AT)

Karl Schwanzer’s Austria Pavilion, built for the 1958 World Exhibition in Brussels, was opened in 1962 as a museum for 20th century art in Vienna. The design for the refurbishment and extension preserves the original appearance; the pre-built vestibule will be demolished. The additional volumes required are situated underground – with the exception of a detached pavilion for porter’s lodge, unpacking room and staff access. A luminous, horizontal glass box – advertising media and lighting – frames the new ensemble.
Due to the new room assignments, the input is mirrored around the central axis. From here, all areas can be reached in a short distance. Shop, café and cinema in the entrance wing, the event rooms with variable room configurations, the exhibition area on the first floor. Wardrobe, sanitary facilities, library and offices are located in the basement. A freight and passenger elevator connects all floors in the main core. A spacious garden courtyard and glass boxes light offices, workshops and library. The depots are situated underneath the parking lot.
The lowered atrium is covered with large-format concrete elements with lawn joints. Part of it is reaches up onto the existing cellar wall. This creates space for a water basin that reflects the sky, doubles the glass façade and separates internal and external areas. The new security pavilion is dressed in black and visually steps back. The exception is a projection screen extending the forecourt. A buffer zone and additional thermal insulation glazing reduce the total energy consumption to an adequate level for a modern building.