18 Princes Street West, Helensburgh

24-28 Princes Street West in Helensburgh is a three-storey, symmetrical seven-bay tenement building designed by William Tait in 1878. The structure is made of cream sandstone ashlar and features modern shops on the ground floor. A modillioned cornice separates the ground and first floors, while a cill course runs beneath the first-floor windows, which are adorned with brattishing and interrupted by canted windows. The building has an eaves lintel course and a bracketted cornice, with bracketted corniced windows on the first floor that have raised margins, chamfered reveals, and moulded off-set lintels. The second-floor windows have corbelled cills and wrought-iron window guards, serving both single and bipartite windows.

On the south elevation facing Princess Street, there is a central entrance with a panelled fanlit door, flanked by modern shops. The centre features a bipartite window on both the first and second floors, with full-height canted oriels on either side and additional windows at the far right and left. Most of the windows are plate glass sash and case. The roof is covered in grey slate, with finialled piended roofs on the canted oriels and corniced sandstone stacks, which include two diamond wallhead stacks on square bases at the centre of the south elevation, mostly retaining their original cans. The building is topped with ashlar coped skews.