High performance

A retractable fabric roof revitalizes the open-air theater at a historic castle in the Austrian Alps

One of the most popular tourist destinations in the Alps, Kufstein village and castle (often called “The Pearl of the Tyrol”), dates from before the 13th century. The medieval Kufstein fortress was built as a defensive stronghold in the steep region of the Alps between Switzerland, Austria and northern Italy’s Tyrol area, and is less than 5km from the German border. After extensive restoration work on the castle and grounds began in 1997, the setting has become a popular attraction and event center for concerts, conventions and weddings.

An inner courtyard of the castle grounds works beautifully as a natural amphitheater and, with added terracing and seating for 4,500, has served well for music concerts, theatrical performances and other events. However, the mountain crevasse that cradles Kuftein is notorious for unpredictable weather and many a performance has been canceled on short notice. To shelter the venue, yet minimize obscuring the spectacular views and to respect the landmark designation of the site, a retractable fabric roof was added.

Kugel + Rein Architekten und Ingenieure, Stuttgart, Germany, designed a radial cable-stayed fabric canopy that opens and closes like an umbrella. The translucent white fabric can be opened or closed in four minutes, extending the active use of the performance space. The pliable fabric is connected at intervals along the radial cables with small trolleys connected to the drive system so when the fabric membrane is contracted, it folds neatly and stores in the center of the web-like cablenet system.

Along the perimeter of the circular structure, scallop cables, together with tangential webbing, connect to the trolleys to adequately tension the fabric when fully extended, thereby removing wrinkles and preventing any ponding areas. Rainwater that falls on the canopy drains down to the sides and is collected along the perimeter in flexible rain gutters.

Christian Hofer, managing director of Kraftwerk Living Technologies, Wells, Austria (a leading European stage and entertainment technologies company) designed and installed the sophisticated sound and light system that augments the Kufstein amphitheater. “The acoustical performance [at Kufstein] is actually enhanced when the roof’s fabric is in place [extended],” says Hofer. “The roof also makes an excellent atmospheric backdrop to the lighting, which can be used to accent and underscore the uniqueness of the structure’s architecture.”