Sitting on its broad lawn, Chepstow suggests the typical summer cottage before the advent of the vernacular and decorative impulses of Stick, Queen Anne, and Shingle styles. The correctly French, flared mansard roof over a heavy, bracketed cornice tops its massively singular block. Every attempt is made here at imposing grandness, as the building is sheathed in smooth, horizontal boards, lending the exterior a hint of simple planar masonry. Chepstow is the kind of substantial residence that George Mason, Sr., designed for a large number of clients throughout the city in the mid-nineteenth century.