How tall is the Petronas Towers?

How tall are the Petronas Towers?

Each of the two Petronas Towers in Kuala Lumpur rises 451.9 m (1,483 ft) to the tip of its spire, the height used on this site. The official Petronas Twin Towers site rounds this to 452 m. Each tower has 88 floors above ground and five below, and the two are joined at levels 41 and 42 by a double-deck skybridge. From 1998 until Taipei 101 opened at the end of 2004, they were the tallest buildings in the world, and they remain the world's tallest twin skyscrapers.

The headline figure is an architectural height under the rules of the Council on Tall Buildings and Urban Habitat (CTBUH), which count spires but not antennas. The towers' main roofs are considerably lower.

About 46 m of the height is spire above the roof. That spire, rather than the roof, is what put the towers at the top of the world rankings.

The 1998 height controversy with Chicago

When the Petronas Towers topped out, the reigning world's tallest building was Chicago's Sears Tower, now Willis Tower. CTBUH lists its architectural height as 442.1 m to the roof, with antennas reaching 527 m. Its top occupied floor, at about 412.7 m, was also well above Petronas's 375 m. By most measures except one, the Chicago tower was taller.

That one measure was architectural top. Under the criteria applied by CTBUH in 1996, a spire is a permanent architectural element and counts toward a building's height, while an antenna is equipment that can be added or removed and does not. The Petronas spires, designed into the towers from the start, lifted them about 10 m above Sears Tower's roof. The ruling was widely debated, particularly in Chicago, and it pushed CTBUH to publish its rankings in several categories. Today the council recognizes height to architectural top, height to the highest occupied floor and height to tip, with architectural top used for the official tallest list.

Designed from an Islamic star

The architect César Pelli gave the towers a form rooted in Islamic geometry, reflecting Malaysia's majority religion. Each tower's floor plan is based on a Rub el Hizb, an eight-pointed star made of two overlapping squares, with circular segments added in the angles between the points to give more usable office space. The result is a plan of alternating points and curves that steps back in tiers as the towers rise, giving them their tapering, faceted profile. The steel and glass facade picks up motifs found in Islamic art, while the structure inside is mostly concrete.

Planning began in January 1992 with extensive wind tunnel and structural testing. The developer, the national oil company Petronas, wanted an icon for a fast-growing capital, and the government required the towers to be completed in about six years. To meet the deadline, each tower was given to a different contractor: Tower 1 (west) to a Japanese consortium led by Hazama Corporation and Tower 2 (east) to a South Korean consortium led by Samsung C&T. The two teams effectively raced each other, and Tower 2 reached the top first.

Foundations deeper than the towers are wide

The site, a former racecourse, posed a serious problem. Test boreholes showed that it sat on the edge of an underground cliff, with decayed limestone on one side and softer rock on the other. The entire project was shifted 61 m so that both towers would sit on the same soft rock. To carry them, engineers bored 104 concrete piles to depths of 60 to 114 m, the deepest foundations in the world at the time, topped with a concrete raft poured continuously from about 13,200 m³ of concrete. Excavation alone required moving around 500 truckloads of earth every night to dig 30 m below the surface.

The superstructure is built of high-strength reinforced concrete rather than steel, partly because importing steel was expensive and partly because concrete damps sway well. Each tower is supported by a central concrete core about 23 by 23 m and a ring of widely spaced super-columns, which leaves large column-free floors. Early in construction, one batch of concrete failed a strength test; a completed floor was demolished, every later batch was tested before pouring, and three concrete plants were set up on site so one bad batch could never halt the work again. The delay reportedly cost about US$700,000 a day.

The skybridge at 170 meters

The skybridge is the towers' signature feature and a working part of the design. It links levels 41 and 42, about 170 m (558 ft) above the ground, and it is 58.4 m long and weighs about 750 tonnes. Rather than being fixed rigidly to the towers, it rests on a two-hinged steel arch whose legs, each 51 m long, are bolted to level 29 of each tower, allowing the towers to sway independently in high winds without tearing the bridge apart. The bridge was assembled on the ground and lifted into place over three days in July 1995.

It also serves as an escape route: in an emergency in one tower, occupants can cross to the other. A full evacuation after a bomb hoax on 12 September 2001 showed that the stairs could not empty both towers at once, so the plan was revised to use lifts as well, and a successful drill followed in 2005. For visitors, the bridge is the "podium" level where you change lifts on the way up.

A timeline of the towers' height

The towers' story is a sequence of height milestones, from the first excavation to the loss of their national record.

The towers held the world record for about six years, a shorter reign than Sears Tower's quarter of a century but longer than the Chrysler Building's eleven months in 1930.

The towers at human scale

A few comparisons help make 451.9 m tangible. The towers are about 258 times the height of a 175 cm (5′9″) adult. The skybridge alone, at 170 m, is higher than the Great Pyramid of Giza, and the roughly 46 m of pinnacle and spire above the main roof is almost as tall as the 49.54 m Arc de Triomphe. The towers contain about 395,000 m² of floor space, and the project cost about US$1.6 billion. Seen from KLCC Park at the foot of the towers, the spires are so far overhead that the skybridge appears to float roughly a third of the way up.

Comparing the Petronas Towers with other skyscrapers

At 451.9 m, the Petronas Towers sit in the middle of the supertall range, overtaken by newer giants but still taller than many famous towers.

The towers no longer dominate their own city. The Exchange 106 overtook them as Malaysia's tallest building in 2019, and Merdeka 118 now rises more than 200 m higher on Kuala Lumpur's skyline. But as a pair, nothing has matched them: the original World Trade Center towers, the previous record-holders for twin skyscrapers, were about 35 m shorter. You can compare any of these at true scale in the 3D height comparison tool.

Visiting the skybridge and observation deck

The official site describes the visit as a ride to the skybridge followed by a trip to the observation deck on level 86 of Tower 2, about 370 m up, with views across Kuala Lumpur. Ticket numbers are capped each day, a policy that began when Petronas started charging for visits in 2010, so booking ahead is wise. Reports put the daily allocation at around 1,000 visitors, with roughly half the tickets sold online and the rest released on the day, which means walk-up visitors in peak season can find the day sold out. The deck on level 86 is the highest point open to the public; above it, the floors narrow quickly into the pinnacle, and the spire that supplies the final tens of meters of height is a structural crown rather than an occupied space. The skybridge visit is short, as groups are moved on in timed slots, but it offers a rare view straight across to the twin tower at the same height. The towers stand above Suria KLCC, a large shopping mall with around 300 stores, and the 17-acre (7 ha) KLCC Park, whose fountain light shows are a popular evening view of the illuminated towers.

The towers are also home to the Petronas Philharmonic Hall, base of the Malaysian Philharmonic Orchestra. For converting the heights in this article, the height converter handles meters and feet, and the landmarks hub ranks the towers among every structure on the site.

What the 451.9 meters represents

The Petronas Towers' height carries more meaning than most. It moved the title of world's tallest building from the United States to Southeast Asia, where it has stayed ever since, passing to Taiwan and then the Middle East. The decision to count spires remains debated, and the towers have long since been surpassed. Yet their 451.9 m, delivered by two rival construction teams on some of the deepest foundations ever built, still makes them the tallest twin buildings on Earth, and their silver silhouette is the defining image of Kuala Lumpur.