Stanislawa (Siasia) Sandecka was born in Poland in 1912. She attended Warsaw Polytechnic and had the opportunity to work in Paris and through a scholarship offered by the French Government. Siasia worked on the Polish Pavilion at the 1937 International Exhibition where some of her graphic work as contribution to the Polish entry, won the Gold Medal for Graphics. Siasia also had the opportunity to work with Le Corbousier at Expo '37 on the photomontage for the Temps Nouveaux and on a model for a stadium.

In 1938 after graduating from Warsaw Polytechnic Stanislawa married Matthew Nowicki. They moved to the United States in 1946 where Matthew was appointed the Chair of the School of Architecture at the University of North Carolina at Raleigh, and Siasia began teaching the first year architecture studio. In the fall of 1951 Stanislawa began teaching the first year studio at the University of Pennsylvania. She used her home, a converted shell of a carriage home as an object lesson for her students. Siasia left for a year to teach at the University of Southern California, but returned to the University of Pennsylvania and continued to teach there until her retirement.