Petronas Twin Towers, Kuala Lumpur

Petronas Twin Towers

Kuala Lumpur, Malaysia

With their majestic silhouette and imposing height, the Petronas Twin Towers celebrate Malaysia’s emergence as a global commercial center while also honouring the country’s cultural heritage. The towers, a modernist take on the traditional Islamic minaret, also represent something of a seismic shift in architecture: They’re the first structures outside the United States to claim the title of world’s tallest buildings, a ranking they held from 1998 to 2004.

Built to house the headquarters of Petronas, the national petroleum company of Malaysia, the towers are extraordinarily slender by engineering standards – a fact that created challenges for Otis.

Without enough space for the conventional configuration of side-by-side elevator hoistways, Otis devised a system of double-deck elevators to reduce the number of hoistways needed. The towers are equipped with 58 double-deck elevators and 18 single elevators.

The towers are clad in panels of glass and stainless steel, creating an effect that architect César Pelli called “multifaceted diamonds sparkling in the sun.”

The floor-plate of each tower is formed by two interlocking squares with small circular infills. These geometric figures are said to symbolize unity, harmony, stability and rationality – all important principles of Islam. The towers feature a series of setbacks as they taper skyward to a height of 1,483 ft.

58

DOUBLE-DECK ELEVATORS

2,170

STEPS

750

TONS

Race to the finish

The Malaysian government specified that construction be completed in six years. To meet the deadline, two building consortiums were hired – one South Korean, one Japanese – with each responsible for one of the towers. The first to finish would win the right to build the skybridge. The South Korean crew claimed victory by completing Tower 2 (the east tower) first.

Skybridge

The double-deck skybridge that hangs between the towers at the 41st and 42nd floors is not directly attached on either end. Instead, it is designed to slide in and out as the towers sway during high winds. It also helps support the swaying towers. The skybridge, 192 ft long, is supported by arches that are bolted to level 29 of each of tower.

The lower level is open to the public, but tickets are limited to about 1,000 people a day. The upper level is reserved for the towers’ tenants. The skybridge connects a conference room, an executive dining room and a prayer room.

Quick facts about the Petronas Twin Towers

At 1,483 ft, the towers were the first buildings outside the United States to claim the title of the world’s tallest, succeeding the 1,450-feet-high Willis Tower in Chicago. They remain the world’s tallest twin towers.

When Tower 2 reached the 72nd floor, engineers discovered it was leaning about 25 millimeters off vertical – or nearly an inch. To correct the lean, the next 16 floors were slanted back 20 millimeters. Surveyors checked verticality twice a day until the building's completion.

Built over a former racetrack, the Petronas Towers also include shopping and entertainment facilities, a petroleum museum and a concert hall that is home to the Malaysian Philharmonic Orchestra.