The Shanghai Tower, currently being built in the business district of Lujiazui, Pudong in China's biggest city, claims it will house the tallest hotel in the world upon completion in 2015.

Located on the 84th-110th floors of the 632m (2,073 ft), 121-storey building, the J Hotel Shanghai Tower will have 258 rooms, a world class spa as well as three restaurants.

It is owned by Shanghai Jin Jiang International Hotels Group and will be operated by Interstate China Hotels and Resorts.

The spiral-shaped building was designed by architect firm Gensler who conducted a series of wind tunnel tests to simulate the impact typhoons would have on the building.

Gensler says the tower is a city within a city comprising nine vertical zones, each 12 to 15 storeys high. Offices will occupy central floors, while the upper floors will house the hotel, cultural venues and an observation deck.

A six-storey retail podium will concentrate shopping and dining near the base of the building, with the ground floor serving as an urban market.

One of the central features of the building, according to Gensler, is the transparent, second skin that wraps the entire building. This design will conserve energy by modulating the temperature within the void.

Jin Jiang Hotels is one of China's leading hotel operators and has more than 900 hotels, providing nearly 136,000 rooms.