17 William Street, Helensburgh

17 William Street in Helensburgh is an earlier 19th-century, two-storey, three-bay symmetrical villa featuring a classical doorpiece. The building is constructed from cream and pink sandstone rubble, with coursed stone on the east elevation and ashlar dressings. It has a base course, raised window margins, and a quoin strip.

The east elevation, facing William Street, has a pilastered doorpiece at the center, complete with a cornice and blocking course, leading to a deep-set half-glazed modern door and red tiled steps. There is a window on both the right and left sides of the door, and three symmetrically arranged windows on the first floor.

The south elevation, facing Princess Street, has two widely spaced bays, each containing a window on both the ground and first floors.

At the rear, the west elevation features a stone forestair leading to a boarded porch on the first floor.

The villa has plate glass sash and case windows, a grey slate roof with ashlar coped skews, and a rendered stack on the south gable.