He continued his education in architecture at the Royal Danish Academy of Fine Arts (Kunst-Akademiets Arkitekturskole) from 1885 to 1888.
[2] After graduation, Zettervall was licensed as an architect and first worked for his father who was chief of Board superintendent for the administration of state buildings (Överintendentsämbetet).
In 1890 he was recruited by Adolf W. Edelsvärd (1824–1919) to work on the architectural office of the Swedish national railway system, Statens Järnvägar.
In addition, he had a number of other commissions including drawing the plans for Suntak Church (Suntaks kyrka) at Tidaholm, the former courthouse at Krylbo (Krylbo tingshus) and the county hall at Sollefteå (Sollefteå tingshus).
[4] [5] [6] Zettervall was influenced by the Richardson style when he designed several railway stations in Sweden during the 1800s.