Petronas Twin Towers

The Petronas Twin Towers (also known as the Petronas Towers or Twin Towers), in Kuala Lumpur, Malaysia are the world's tallest twin buildings. 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).
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 exceed the height of the roof and highest floors of the Petronas Twin Towers. The Sears Tower’s tallest antenna is about 250 feet (76 meter) 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. Hence, surpassing the roof of the Sears Tower by 10m.