30 St Mary Axe
London, United Kingdom
- The outside of the building consists of 24,000 square metres of glass arranged in diamond-shaped panes.
- The 23 lifts vary in velocity from 1 metre per second to 6 metres per second.
- Windows in the lightwells open automatically to augment the air conditioning system with natural ventilation, an occurrence anticipated to save energy for up to 40% of the year.
- The floor plan is rotated for each successive floor, creating a series of spiraling 5-storey atria that stretch the full height of the building.
- In spite of the tower's completely rounded shape, the only curved piece of glass is at the very top. Known as the "lens", it weighs 250kg (550 pounds) and is 2.4 metres (7.9 feet) in diameter.