Although he was ten years old when the Bauhaus was closed, Seidler's analysts invariably associate him with the Bauhaus because he later studied under emigrent Bauhaus teachers in the USA. He attended Harvard Graduate School of Design under Walter Gropius and Marcel Breuer on a scholarship in 1945/46, during which time he did vacation work with Alvar Aalto in Boston drawing up plans for the Baker dormitory at MIT. He then studied visual aesthetics at Black Mountain College under the painter Josef Albers in mid 1946.
Seidler's parents migrated to Sydney in 1946, and (while he was working for Breuer in New York) in early 1948, his mother wrote to him to commission him to come to Sydney to design their home. Seidler arrived in Sydney on 20 June 1948 (which was a few days before his 25th birthday) , with no intention to remain in Australia, but to stay only until the house was finished. The house became known as the Rose Seidler House (1948–1950), in Wahroonga, in remote bushland of a suburb on Sydney's Upper North Shore. This project was the first completely modern domestic residence to fully express the philosophy and visual language of the Bauhaus in Australia and won the Sulman Award of 1951. From the huge publicity of this house, others approached Seidler to design their homes. With so many clients and his enjoyment of the Sydney climate and harbour views, Seidler decided to stay in Australia. The Rose Seidler House became a house-museum in 1991.