Broad Group, a Chinese company best known for making air-conditioners, is drawing up plans to build the world’s tallest skyscraper in just three months, using prefabricated blocks that are slotted together like Lego bricks.

Broad describes the construction technique as “the most profound innovation in human history”. Others wonder if “reckless” might be more apt. But Broad is deadly serious and, having completed a reassuringly solid 30-storey building in a mere 15 days last year, maybe its skyscraper dream is not so crazy after all.

If built, Broad’s tower will reach 838 metres – 10m higher than the world’s tallest building at present, Dubai’s Burj Khalifa. While the Burj took nearly six years to complete, Broad wants to build its 220-storey skyscraper at a rate of about two storeys a day.