 New power and water systems and gas heating were established and the coal-powered bakery and kitchens were introduced to electricity.Between 1925 and 1926 the hotel's guest capacity was expanded under the guidance of architects Heidenreich und Michel.In 1927/28, under the direction of architect Johann Emil Schaudt (1871–1957), an 1800 m² area of the hotel cellars was transformed into a spa.