From 1907 to 1914 he was director of the design department at the United Workshops for Art in Craftsmanship in Munich, a pioneering force in the interior design and decoration of the era. The focus was on craftsmanship, redesigning the everyday living environment, and making functionality visible. It was during this period that he produced furniture designs that are still prized today. His most famous piece is one of them: the Nymphenburg coat rack from 1908. In 1909, Blümel met the writer Hermann Hesse and, in the following years, designed several book covers for him. Otto Blümel was owner of the “Verdienstkreuz am Bande der Bundesrepublik Deutschland” cross of merit.