The Neff and Schmidt houses are standard Harmonist houses, that is, simple, two-story brick houses with three-bay facades of two windows followed by a door. The interior consists of a single large room on both the first and second floors. The Harmonists used locally available materials like log, brick, and stone, instead of the traditional German building technique of half timbering with stucco-covered wattle and daub walls. The Harmonists in Butler County favored solid brick exterior walls and heavy timber, with brickinfill interior walls covered with plaster. They did, however, continue to use Dutch biscuits (as in the 1805 Harmonist barn at 303 Mercer Road). With the exception of renovated windows and other minor changes, both houses maintain their architectural integrity.