Dubai to open world's tallest building

The world's tallest building is set to be opened in the Gulf emirate of Dubai.

More than 800m (2,625ft) high and clad in 26,000 glass panels, Burj Dubai has 160 floors and more than 500,000 sq m of space for offices and apartments.

Construction began in 2004, at the height of an economic boom. The opening comes after a financial crisis which has seen Dubai bailed out by Abu Dhabi.

The exact height of the $1.5bn tower is secret, but it far exceeds that of the previous record holder, Taipei 101.

It will also lay claim to the highest occupied floor, the tallest service lift, and the world's highest observation deck - on the 124th floor. The world's highest mosque and swimming pool will meanwhile be located on the 158th and 76th floors.

Technical challenges

Though not complete on the inside, Burj Dubai will be officially opened by Dubai's ruler, Sheikh Mohammed Bin Rashid Al Maktoum, at 2000 (1600 GMT) on Monday, 1,325 days after excavation work started.

At a ceremony to be attended by 60,000 guests, Sheikh Mohammed will also reveal the exact height of the tower that dwarfs the 508m Taipei 101 and the 629m KVLY-TV mast in the US, the tallest man-made structure. Its spire can been seen from 95km (60 miles) away.

"We weren't sure how high we could go," said Bill Baker of Skidmore, Owings & Merrill, the building's structural engineer. "It was kind of an exploration... a learning experience."

Mohamed Ali Alabbar, chairman of Emaar Properties, the developer behind Burj Dubai, told the BBC that the building's design had posed unprecedented technical and logistical challenges, not just because of its height, but also because Dubai was susceptible to high winds and was close to a geological fault line.

"We have been hit with lightning twice, there was a big earthquake last year that came across from Iran, and we have had all types of wind which has hit us when we were building. The results have been good and I salute the designers and professionals who helped build it," he said.

The design incorporates ideas from traditional Islamic architecture, while the open petals of a desert flower were the inspiration for the tower's base.

Burj Dubai will be home to 1,044 luxury apartments, 49 floors of offices and eventually a 160-room Armani-branded hotel. Around 12,000 people are expected to live and work in the tower, which is part of a 500-acre development.

However, investors are facing losses even before the tower is completed because property prices in Dubai have slumped amid the global economic crisis.

Some apartments were selling for $2,700 per sq ft, but are now going for less than half that. Analysts say it will be particularly hard to lease office space because few companies can justify paying premiums for luxury.

Emaar's government-owned parent company, Dubai World, meanwhile recently had to request a suspension in debt repayments, and Dubai had to turn to Abu Dhabi last year for bail-outs worth $25bn.

The BBC's Malcolm Borthwick in Dubai says developers are holding back on new flagship projects, so Burj Dubai could mark the end of an era for skyscrapers in the Gulf - at least in the short term.