Pynhannot House, 49-51 Colquhoun Street, Helensburgh

Pynhannot House is a large villa dating from 1875, with substantial additions made in 1902 by Robert Wemyss. It is a two-storey building over a raised basement, originally six bays in width, exhibiting a Regency style porch and a distinctive Glasgow-style corner tower. The exterior is largely cream-coloured sandstone, roughly squared and snecked on the south elevation, with ashlar stone dressings. A base course, chamfered corners, and ashlar mullioned windows (bipartite and tripartite in design) are present, along with bracketed eaves.

The south (entrance) elevation features two full-height canted windows centrally placed, connected at the first floor by a balustraded balcony and consoled eaves above. Parapets break the eaves above each canted window, with a gable in the centre and pierced stone decoration beneath. A pilastered, corniced doorway is located to the right, with a blocking course, a fanlit, two-leaf door, a half-glazed vestibule door, and a glass canopy porch supported by timber columns. A window sits above the doorway on the first floor. A slightly projecting bay to the outer right has a finialled, semi-circular headed gable that breaks the eaves, a corniced bipartite window at ground and first floors, a dentilled cornice above the first-floor window, and a raised central inscription reading "1902". A circular window is positioned at ground level to the left of the canted windows, with a corresponding window above on the first floor. An engaged circular angle tower is on the left side, featuring bipartite windows at ground and first floor levels within an advanced panel. A cornice sits at ground level, an apron below the first-floor window also inscribed "1902", and scrolled decoration above the gabled cornice at the first floor. Windows flank the tower at ground and first floor levels. The roof is bell-cast, with small dormers featuring curvilinear gablets, topped by a weathervane with a ship finial.

The east elevation has a window to the centre at ground level, a small window to the right, and a bipartite window at the outer right, with a window to the outer left. The first floor displays a window off-centre to the right, a bipartite window to the outer right, and a window to the outer left.

The north (rear) elevation has a round-headed stair window in the centre, set against a lower, two-storey stair block.

The west elevation presents an engaged tower to the outer right and a window at ground level to the centre. A doorway is located to the outer left, with chamfered arrises, a fielded panelled door, a segmental-arched dentilled cornice, and a window above it on the first floor. The windows throughout are plate glass sash and case windows. The roof is covered with grey slate, with corniced rendered stacks.

The interior boasts fine Burma teak fireplaces in the principal reception rooms, with an Art Nouveau style in the drawing room. Features include corniced ceilings, wainscot to an axial corridor and the drawing room, a timber beamed ceiling in the drawing room, and original door fittings.

The property is approached via cream ashlar gate piers with pyramidal caps, and the rear is enclosed by sandstone rubble boundary walls.