Shanghai Tower, which will be China's tallest building when it is completed in 2015, will reach its highest point tomorrow, adding to the country's construction boom even as the economy slows. The 632-metre Shanghai Tower in the city's Pudong business hub is also set to be the world's highest building after the 828-metre Burj Khalifa in Dubai, according to the Chicago-based Council on Tall Buildings and Urban Habitat. The 125-storey Shanghai Tower, which broke ground in November 2008, will include offices, a luxury hotel and retail space, according to the developer, Shanghai Tower Construction and Development. "We could have built taller technically, but we didn't aim for physical height when we planned the building," Gu Jianping, the president of Shanghai Tower Construction & Development, said at a press conference in Shanghai yesterday. The new tower integrates with two nearby skyscrapers: Jin Mao Tower and Shanghai World Financial Centre, he said. At 492 metres, Shanghai World Financial Centre, also in Pudong, is currently the mainland's tallest building. Competition to build the country's skyline higher is continuing even as the economy slowed for a second quarter and Premier Li Keqiang reins in a credit boom. Twenty-two buildings higher than 200 metres were completed on the mainland last year, accounting for 33 per cent of the global number, more than any other country, according to the council. The vacancy rate for prime offices in Shanghai rose to 6.2 per cent in the second quarter compared with 4.3 per cent at the same time last year, the eighth lowest among 29 cities tracked by Cushman and Wakefield in the Asia-Pacific region. Office rents fell 4.5 per cent from a year ago to US$450 per square foot a month, it said. The 660-metre Ping An Finance Centre in the southern city of Shenzhen will be China's tallest building when it is completed in 2016, according to the skyscraper centre database of the council on tall buildings. The developer of Shanghai Tower will hold a topping-out ceremony today to mark the placement of the last beam on the building's main structure.