17, 19 John Street, Helensburgh

17 and 19 John Street in Helensburgh is an earlier 19th-century, two-storey and attic, three-bay tenement building that features a shop at ground level. The exterior is rendered and lined to resemble ashlar, with ashlar dressings and painted surfaces. It includes base and eaves lintel courses, raised margins, and tripartite windows with stone mullions.

On the east elevation facing John Street, there is a slender columned doorpiece at the center topped with an entablature, leading to a fanlit two-leaf panelled door. To the left is a tripartite window, while to the right is a timber pilastered two-bay shop front. This shop front has a modern door on the left and a shop window on the outer right, flanked by pilasters, with a modern fascia and cornice above. The first floor features a window in the center, with tripartite windows on either side.

The north elevation facing Princes Street West has a window at both ground and first floor levels. The rear elevation features a projecting curved stair tower at the center, topped with a cat-slide roof, and a door on the return to the left.

The building displays a variety of glazing patterns, mostly consisting of replacement windows, with small-pane sash and case windows in the ground floor tripartite window on the east elevation. The roof is covered with grey slate, and there are rendered corniced stacks at the gables, along with a full-width slate-hung modern dormer on both the east and west elevations.