Rialto Towers
Rialto is a skyscraper located at 525 Collins Street, in the western side of the Melbourne central business district, Victoria, Australia. It was the tallest office building in the Southern Hemisphere when it was constructed.
The Rialto featured Melbourne's first skyscraper public observation deck, which operated between 1994 and 31 December 2009. It was also the location of Melbourne's first Tower running event.
Background
The site of the whole Rialto development ran between Flinders Lane and Collins Street, and was occupied by several buildings including numerous small warehouses on Flinders Lane, with lanes between including and Winfield Square and Robbs Lane. On the corner of Collins and King Street stood Robb's Buildings, named for the owner, railway builder John Robb, a grand classical styled 5-storey Victorian office building designed by Thomas Watts and Sons in 1885, and one of the largest in the city at the time. Next to that along Collins Street stood two interwar buildings, then the Rialto Building designed by William Pitt and the Winfield Building designed by Charles Debro & Richard Speight, both part of the five building Rialto building group, an historic streetscape along Collins Street running up to the 1880s Olderfleet Building to the east.Through the late 1960s and early 1970s, National Mutual Life Association of Australasia purchased the various historic buildings on the site, but had to rethink plans when the Rialto and Winfield buildings were listed by the new Historic Buildings Preservation Council in 1974, and the National Trust of Victoria opposed the demolition of other buildings on the site.
Little progress was made until 1980 when the site was acquired by Grollo Australia in a joint venture with St Martin's Properties. Grocon successfully argued that Robb's Building stood in the way of its major three-tower proposal, which they modified to a two-tower proposal, but still demolished the Robbs building. A hotel was created utilising the whole of the long rear wing of the Rialto Building, the replacement of the rear wing of the Winfield Building, and the creation of an atrium between.
Construction
The final development plan involved several separate projects proceeding concurrently: the 242m office tower; a five-level underground car park; the restoration of the historic Rialto and Winfield building to create an international hotel; and a theatrette. Ancillary works included the Collins Street Plaza, restoration of the York Butter Factory and Robbs Annexe, and new shops.Designed by architects Gerard de Preu and Partners in association with Perrott Lyon Mathieson, the building was built between 1982 and 1986, opening in October 1986. The massive glass curtain wall façade of reinforced blue tinted mirrored glass is its central feature and changes colour during the day, ranging from a trademark dark blue to a brilliant gold during sunset.
Consultants for the design were Dino Burranti, Richard Falkinger, Meldrum Burrows and Partners and Davenport Campbell and Partners. Lincolne Scott Australia provided the mechanical, electrical, and fire services as well as the elevators. The hydraulic engineers were C. R. Knight and Associates.
Project planning was undertaken by Project Planning and Management Pty Ltd and the quantity surveying/cost consultants were Rider Hunt and Partners. The structural engineers for the project were W. K. Meinhardt and Partners and Bonnaci Winward.
It is high, with 55 floors and 3 basement floors. It comprises two conjoined towers, the shorter North Tower being high with 43 floors. In total, there are of office space. Early tenants moved into the lower floors while the upper floors were still under construction in 1984.