Petronas Towers

PETRONAS took the challenge to develop the PETRONAS Twin Towers in 1991.

The project is an integral part of the Kuala Lumpur City Centre (KLCC), a carefully planned development to provide the capital city with an efficient and modern centre for urban activity, trade and commerce encircling a vast, open green lung. It brought together the world's leading practitioners of engineering, building technology and construction.

The Petronas Twin Towers were the world's tallest buildings, before being surpassed by the Taipei 101. However, the towers are still the tallest twin buildings and office building in the world. Tower 1 was built by Hazama Corporation and Tower 2 by Samsung Engineering & Construction and Kukdong Engineering & Construction (both of South Korea).

They were the world's tallest buildings from 1998 to 2004 if measured from the level of the main entrance to the structural top, the original height reference used by the US-based Council on Tall Buildings and Urban Habitat from 1969 (three additional height categories were introduced as the tower neared completion in 1996). With its unique structural and engineering breakthrough, the Petronas Towers is most certainly a man made marvel.

No doubt the Petronas Towers is one of the tallest buildings of the 20th Century and still the tallest twin towers.

But it is unique not because of its record-breaking height, but its ability to capture and represent the aspirations of Malaysia in a uniquely Malaysian way - symbolism.

It holds an iconic status for this very reason, and this symbolic meaning coupled by its engineering achievements makes the Petronas Towers a man made marvel.

The Petronas Twin Towers were the tallest buildings in the world until Taipei 101, as measured to the top of their structural components (spires, but not antennas), took over the record. Spires are considered integral parts of the architectural design of buildings, to which changes would substantially change the appearance and design of the building, whereas antennas may be added or removed without such consequences. The Petronas Twin Towers remain the tallest twin buildings in the world.

The Sears Tower and the World Trade Center towers were each constructed with 110 occupied floors - 22 more than the Petronas Twin Towers' 88 floors. The Sears Tower and the World Trade Center's roofs and highest occupied floors substantially exceeded the height of the roof and highest floors of the Petronas Twin Towers. The Sears Tower's tallest antenna is 75 m (246 ft) taller than the Petronas Twin Towers' spires. However, in accordance to CTBUH regulations and guidelines, the antennas of the Sears Tower were not counted as part of its architectural features. Therefore, the Petronas Twin Towers exceed the official height of the Sears Tower by 10m, but the Sears Tower has more floors with occupied office space at a higher level.

The diamond-faceted facade and external architectural details give the PETRONAS Twin Towers a unique articulation and form. Comprising of 83,500 square metre of stainless steel extrusions, the specially designed 33,000-panel unitised curtain wall cladding system is tailored to suit the Towers. The choice of stainless steel not only reflects the hi-tech industrial ideal of Malaysia, but also the lustre of the tropical sun.

Complementing the stainless steel is 55,000 square metre of 20.38 mm laminated glass designed to minimise heat gain by reflecting harmful UV light and unwanted solar radiation. This greatly assists in ensuring that the internal spaces of the office buildings are maintained as a comfortable working environment. More direct sunshading devices are built into the highly intricate facade design of 'teardrop and 'bullnose' steel sections which frame and line the open glass areas. These elements also provide a distinctive play of shadow and line over the facade of the buildings.

The PETRONAS Twin Towers' pinnacles, made of structural steel, stand 73.5m tall. Each pinnacle took over 19 weeks to fabricate. One was fabricated in Japan and the other in Korea, while the primary structure was manufactured locally in lpoh, Perak, and Sungai Buloh, Selangor. Three days of hydro-jacking set the pinnacles almost half a kilometre above the city of Kuala Lumpur to the exacting tolerance of 30mm in line with the Towers below.

The pinnacles play an important part in both the aesthetics and functionality of the Towers. The timeless minaret design is a crowning symbol of the country and its culture. However, the more urbane functions of housing aircraft warning lights and window washing equipment for the Towers are also stored within the pinnacle assembly.

Each pinnacle is composed of a spire, mast ball and ring ball, which are in turn made up of 50 unique elements, interlocked into single 176-ton pieces. Thus from the ground to the pinnacle-tips, the Towers are an embodiment of state-of-the-art engineering and visionary design.

The Skybridge, a major attraction at the PETRONAS Twin Towers, symbolises a gateway to the future and is used to facilitate movement between the two towers. It can also function as an escape route in case of emergencies.

The Skybridge is supported by a "three-hinged arch" consisting of giant round bearings at the base and a pair of legs 51 metres in length. The base of the arch is located at level 29 of each tower. The cylindrical legs are bolted to a box girder below the centre of the double-decked bridge.