Perth Telephone Exchange, 1-5 Canal Crescent, Perth

The Perth Telephone Exchange, built between 1957 and 1960, was designed by the HM Office of Works with Alfred Charles Shallis as chief architect. The building comprises an L-shaped plan with a two and three storey exchange block and a four storey curved and glazed administration and office wing adjoining to the west and slightly set back from the street. A third floor was added to the exchange wing around 1970 by the Dundee-based architects Baxter, Clark and Paul.

The structure employs a reinforced concrete frame with square concrete columns and floors. A polished black stone base course runs along the building. The exchange wing is predominantly rendered with smooth margins featuring picture windows. The south end wall and part of the west wall of the exchange wing, and the west end wall of the office wing, are clad with roughly squared, snecked and tooled red sandstone.

The curved administration and office wing displays a full height metal-framed glass curtain wall on its front and rear elevations, except at ground floor level on the rear elevation which is rendered. Each bay contains four windows separated by full-height concrete fins, with infill panels positioned above and below the glazing. The entrance, accessed by steps, is positioned off-centre to the right and features two-leaf timber doors flanked by timber side panels beneath a zig-zag cantilevered timber canopy. The fourth floor window in the west end wall is slightly advanced. The exchange wing's west wall contains door openings at each floor, each with a ledge, positioned slightly off-centre to the left.

A diamond-pattern arrangement of cobbles and setts paves the area in front of the building.

The Perth telephone exchange was the fourth largest in Scotland by 1934. Its predecessor occupied the General Post Office building on the High Street, following early practice for telephone exchanges. Discussion of a purpose-built exchange began around 1937 when the Post Office sought a suitable site. By 1939, newspaper reports confirmed that land off Canal Crescent, including a brewery site, had been sold to the General Post Office for the new exchange. The Second World War appears to have delayed construction.

The 1970 extension by Baxter, Clark and Paul carefully replicated the original building's style and architectural detailing, making the addition visually seamless at first inspection.