Sirén was born in 1889 in Ylihärmä. In 1907, he graduated from high school and started his studies at the Helsinki University of Technology. After receiving his diploma in 1913, Sirén worked for Jung & Fabritius until 1917.
Sirén's life path: born in Ylihärmä (1889), graduated from high school (1907), studied at the Helsinki University of Technology (graduated 1913), worked for Jung & Fabritius until 1917.