In 1920 the house was purchased by Wright's sister, Jane Porter, and her husband, Andrew, who converted the two-story home into a duplex in the 1930s, with each floor separated into apartments. The Porters stayed in the Heurtley House for 26 years. Two subsequent owners altered the home further: the kitchens and bathrooms were modernized, the front loggia enclosed, and a black iron gate was added to the entryway. In addition, a master bathroom was added in the last fifteen feet of the main floor veranda, the living room inglenook and dining room breakfront were removed, and a second chimney and furnace were added.