Philadelphia is famous for its Federal-style architecture, its Art Deco landmarks, and its vernacular row houses, but this Center City abode, owned and designed by American architect Frank Weise, looks very different, blending postmodern and modernist styles.

Weise studied under Louis Kahn and Walter Gropius and lived at the Philadelphia property from 1954 until his death in 2003, first as a tenant and then as an owner. Constructed in 1865, it was originally stables and later converted into a home, which Weise adapted and modernised over his stewardship using modernist and postmodernist design principles.

Most unique is its tripartite façade, which features three distinct sections: the recessed first storey with its two entrance doors and columns; the second storey with four rows of arched windows; and finally, a third-storey terne metal mansard with six windows, mixing round and pentagonal shapes in an unorthodox postmodern fashion.

Inside are Weise’s signature curved surfaces, notably two spiral staircases that connect the lower level, which the architect used as a studio and office space, and living spaces above. In total, the rowhouse offers three bedrooms and one-and-a-half bathrooms, with kitchens on the second and third floors and a large roof terrace crowning the property, which was an evolving ‘work in progress’ during the architect’s lifetime.

It was added to the Philadelphia Register of Historic Places by the Philadelphia Historical Commission in 2023, with the nomination stating that ‘307 S. Chadwick St. represents [Weise’s] most significant work and one that allowed him to evolve as a designer.’

Melanie Stecura and Franz Rabauer of Sotheby’s International Realty are listing the unique historic home for $3.5m.

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