Born in Elberfeld, Troost attended the Technical College of Darmstadt and, upon finishing his course, worked with Martin Dülfer in Munich. In about 1904, he opened his own architectural office and became a member of the modernist Deutscher Werkbund association. Troost designed several rooms of Cecilienhof Palace in Potsdam; he graduated from designing steamship décor for the Norddeutscher Lloyd shipping company before World War I, and the fittings for showy transatlantic liners like the SS Europa, to a style that combined Spartan traditionalism with elements of modernity.