Now, construction is officially beginning on what will be one of the most complex infrastructure projects in Singapore’s history. Spanning 1,080 hectares worth of land, almost the size of Changi Airport today, T5 is, in many ways, building an entirely new airport.
Source: https://nowboarding.changiairport.com/discover-changi/first-look-at-changi-airport-terminal-5-key-features.html