Allendale Square, High-rise office building in Perth, Australia

Allendale Square is a 32-storey office tower at the corner of St Georges Terrace and Sherwood Court in Perth. Completed in 1976, it rises 132 metres and occupies only a quarter of its 4,053-square-metre site. The building is rotated 45 degrees to the street, and its stepped walls form V-shaped protrusions; windows are only on the north and south faces, while the rest is clad in 400 tonnes of aluminium panels.

The tower was built in 1976 and marked a moment of vertical expansion in Perth. The building held its position as the city's tallest structure only briefly before being surpassed by St Martins Tower a year later.

The site at St Georges Terrace and Sherwood Court was owned by the Leake family from 1829. At the tower's official opening on 3 August 1976, Premier Sir Charles Court presided and descendants of the Leake family attended. The building's name, Allendale Square, recalls this early colonial association.

The tower occupies only a quarter of its 4,053-square-metre site, so the plaza around its base is open to walk through. The main entrance faces St Georges Terrace at the corner with Sherwood Court. A lift links the lobby to the 99-bay basement car park, and the complex connects to an underground shopping centre and the seven-storey Allendale II building at the rear.

The aluminum cladding was installed through an innovative method carried out almost entirely from inside the building without external scaffolding. This unusual construction technique demonstrated advanced engineering practices when the tower was completed.