Le Corbusier taught at his old school in La-Chaux-de-Fonds during World War I, not returning to Paris until the war was over. During these four years in Switzerland, he worked on theoretical architectural studies using modern techniques. Among these was his project for the “Dom-ino” House (1914–1915). This model proposed an open floor plan consisting of concrete slabs supported by a minimal number of thin, reinforced concrete columns around the edges, with a stairway providing access to each level on one side of the floor plan.
This design became the foundation for most of his architecture for the next ten years. Soon he would begin his own architectural practice with his cousin, Pierre Jeanneret (1896–1967), a partnership that would last until 1940.