Once-bustling Dubai will open the world's tallest skyscraper on Monday, boasting new limits in design and construction, hopeful of polishing an image tarnished by the debt woes afflicting the Gulf emirate.

Emaar, the giant property firm part-owned by the government and which developed the needle-shaped concrete, steel and glass structure, has declined to reveal Burj Dubai's exact height.

Apparently wanting to maintain the suspense, the company will say only that the tower exceeds 800 metres (2,640 feet), putting it far higher than Taiwan’s Taipei 101 tower (508 metres).

Bill Baker, a structured and civil engineer and partner in Chicago-based Skidmore, Owings and Merrill (SOM), which designed the tower, said Burj Dubai has set a new benchmark.

"We thought that it would be slightly taller than the existing tallest tower of Taipei 101. (Emaar) kept on asking us to go higher but we didn't know how high we could go,” he said.