London's Crystal Palace, the largest building in history, went up in just 24 weeks

London's Crystal Palace, about 600 metres long and 150 wide, was built in roughly 24 weeks between 1850 and 1851. Joseph Paxton's design was approved in July 1850 and the building was ready for the opening of the Great Exhibition on 1 May 1851.

## A giant greenhouse for a world fair

The Crystal Palace was erected in London to house the Great Exhibition of 1851. Its dimensions were around **600 metres** long by **150** wide, a scale never before seen in an iron and glass building. **Joseph Paxton's** final design was approved in July 1850 and construction was completed in about **24 weeks**, some **190 days**.

The works involved around **5,000 workers**. For the time it was an absolute record: no structure of that size had ever been raised so quickly.

## Standardized screws and prefabricated parts

The key was modular construction. The iron and glass parts were manufactured off site and then assembled, like a giant meccano set. The **Whitworth** system of standardized screws and nuts allowed lightning-fast assembly, with no piece-by-piece hand fitting.

That method anticipated what we today call prefabrication. Without it, 24 weeks would have been impossible. The building was conceived as a temporary exhibition hall, not a permanent structure.

## A "temporary" building that defined an era

The Crystal Palace was conceived as a provisional venue for the exhibition. Its futuristic image for the time, with nearly a million square feet of glass and iron, contrasted with its ephemeral nature. Over time, the structure was dismantled and moved to another location, and was eventually destroyed by fire in 1936.

Some claim that its disappearance and the circumstances of the fire do not quite fit the official account. That suspicion circulates online, but it is not supported by documentary evidence. What is verifiable is the other thing: a **600-metre** building raised in **24 weeks** with **5,000** workers and standard screws.