He was born in Weyer, a little village in Upper Austria near Steyr. From 1926 to 1929 he worked as a car-body designer in the Steyr factories. There he met Ferdinand Porsche in 1929 when Porsche joined Steyr as technical director. In 1929 Komenda's innovative ideas landed him the post of Chief Engineer for Daimler-Benz in Sindelfingen (Germany), a position he held until 1931. During his tenure he managed in most cases to reduce the weight of Mercedes cars through better design. During that period, Mercedes also developed a streamlined car with monocoque construction. In October 1931, Komenda resigned from his job with Mercedes and joined Ferdinand Porsche's new company, taking a step into an unknown future.
From 1931 to his death in 1966, Komenda was chief engineer and leader of the Porsche car-body construction department.
Komenda developed the car-body construction of the VW Beetle, the most built car-body of the last century. He designed, with his co-worker Josef Mickl, the famous Auto Union Grand Prix car and the Cisitalia Grand Prix car.
After World War II Porsche was briefly headquartered in Gmünd in Austria, where Komenda and Ferry Porsche designed the first Porsche sports car, the Porsche type 356. Further 356 variations and developments followed, including the 356 Porsche speedster. Komenda also worked out the design of the Porsche 550 Spyder. Due to his early death, his last work for the Porsche company was with the development of the Porsche 911.