St. Joseph's Church, designed by Cleveland architect George Stickle, was intended to be the cathedral for the New Castle–Sharon Diocese, and the church and its rectory planned for a bishop and his staff. The church is an irregular octagon of Indiana limestone pierced on all elevations by full-height, hooded, arched windows. At the pinnacle of the pyramidal, stainless steel roof, a circular cupola with a fluted roof is surmounted by a narrow, elongated spire supporting a statue of the Risen Christ; the latter was placed there by a helicopter. A statue of St. Joseph welcomes parishioners above the triple doors facing E. State Street.

The new diocese never came to be, and in 1995–1996, the church was reconfigured by Weborg, Rectenwald Architects to accommodate St. Joseph's parish. As designed, the church seated 968, with rows of seats facing north toward the recessed altar. After 1996 and in response to the liturgical recommendations of Vatican II, the seats were broken into three sections around a raised communion table brought forward nearly to the middle of the church. The space of the former altar became a meditation area, and a new entrance on the east elevation creates space for socializing before and after worship.