Zelie Basse and her husband, Philipp L. Passavant, built a two-room-over-two-room brick house on S. Main Street, which they promptly outgrew. An addition was made to the east elevation in 1810 and, subsequently, the double porch of this addition was enclosed. In c. 1910, the family hired Pittsburgh architect Frederick J. Osterling, who had relatives in the area, to add bay windows and a grand Colonial Revival porch to the north elevation. It was probably at this time that all the windows were enlarged. The name Passavant, synonymous with philanthropy in Lutheran circles, refers to Zelienople native William A. Passavant (1821–1894), Philipp L. and Zelie's son, who founded hospitals, orphanages, and homes for seniors in a dozen places in the United States between 1849 and 1893, including the Orphans Home and Farm School, now Glade Run ( BU28), in Zelienople.
A few doors north, another German émigré, Christian Buhl, built a two-and-one-half-story brick house in 1805, which, with the exception of the 1940s two-story addition to the west (rear) elevation, has not been substantially altered (221 S. Main Street). The interior is unusually spacious for the period, with wide stairwells and a full third floor. Both houses are open to the public under the auspices of the Zelienople Historical Society.