She and her husband Heikki Siren set up their own architectural office in 1949.
The Sirens worked together as architects their entire life.
The Otaniemi Chapel is noted for its delicate balance between features of Finnish rural architecture and a modernism, influenced by Alvar Aalto's redbrick period of the 1950s.
Their later work is noted for its monumentality.She is buried in the Hietaniemi Cemetery in Helsinki.