thick raft foundation sits nine metres below the ground level. Approximately 57,000 tonnes of concrete and 6,000 glass panes for the curtain-wall structure were required. Over 8,000m2 of rigid insulation board by Kingspan was used to reduce heat loss. The curtain-wall structure is clad in glass, and elements were added to counter excessive light. Louvres on south-facing windows allow for the control of daylight and sunlight into its interior. On the west- and east-facing sides, aluminium strips which are noticeable from ground level project outwards to provide shading from the sun. The louvres on the south façade alter its consistency and appearance when some are open and others are closed. They stop excessive passive solar gain. Ultraviolet light hits the glass and is changed to infrared which generates heat through radiation, creating overheating. The tower has 47 floors and is 168.87 metres (554 ft) in height, making it the tallest building in the United Kingdom outside London, and the tallest building in Manchester, until it was surpassed by Deansgate Square. Floors 1 to 22 are occupied by the 279-bedroom four-star Hilton Manchester Deansgate Hotel. The 23rd floor has a four-metre cantilevered overhang with two glass windows in its floor, overlooking the ground from the skybar, Cloud 23. The floor has a bar and lounge operated by Hilton. Floors 25 to 47 are occupied by residential apartments. A 12-storey office block is planned next to the tower, with 6,506 square metres of floor space. The hotel has a four-storey annexe, containing a swimming pool, ballroom, conference rooms and coffee shop. Occupancy The architect, Ian Simpson, lives in the top floor penthouse, the highest residential space in Europe after surpassing Lauderdale Tower at the Barbican Estate in London upon opening in 2006. It cost £3 million and occupies the top two storeys. It has a semi-indoor garden containing 21 four-metre-tall olive, lemon and oak trees, originating from Italy and lifted into place with cranes through a small aperture in the roof before it was glazed in 2006. The Hilton Manchester Deansgate occupies space up to level 22, and a four-metre cantilever marks level 23 where the Cloud 23 bar is located. Above this level are apartments from level 25 to the triplex penthouse apartment on level 47. Beetham claimed 90% of the residences were sold before construction began in 2004. The Daily Telegraph claimed that 55 of 219 apartments were waiting to