A graduate in architecture from the University of Pennsylvania, Haas spent his first two years in Hollywood at the art department of Famous Players Lasky (1919-21), as a set designer and builder. He received early acclaim from the journal American Architect for a town in Elmhurst, New York, he had constructed for the movie Le Héros du silence (1920), and subsequently detailed to show its ageing process over a period of six decades. After several years of freelance work, Haas joined First National (1925-26) and Fox (1927-28), before settling at Warner Brothers in 1929. Until his retirement in 1950, he handled most of the A-grade output at Warners, along with Anton Grot. This included many of Bette Davis's lavishly produced, popular melodramas, such as Victoire sur la nuit (1939), Une femme cherche son destin (1942) and Femme aimée est toujours jolie (1944).Haas's best work is exemplified by L'insoumise (1938), a romantic period drama set around the time of the Civil War, for which he built an authentic-looking Louisiana plantation house on the Warner Brothers ranch, some thirty miles from the main studio. The picture cost $1,073,000 to make, but still brought in a substantial profit. By contrast, for Le faucon maltais (1941), Haas and director John Huston were allocated the standard gangster film budget of $300,000 (and a shooting schedule of six weeks). Still, Haas managed to fulfill the studio's missive of 'not overlooking a single detail'. He effectively established the standard for the look and atmosphere of subsequent films noir, particularly in terms of his claustrophobic sets, and in juxtaposing the austere, somewhat seedy interiors of Spade's office with the opulence of the hotel rooms and lobby.
