Designed to be nearly half a kilometre long, 30 storeys high and to play host to upwards of 120 personnel, the behemoth will be one of the largest vessels ever sent to sea and will displace the same amount of water as six of the world's largest aircraft carriers.

All in all, 14 modules will be finished off and pieced together to form the top half of the vessel.

For such a mammoth task, it's the tiny intricate details that make all the difference, as evidenced in Shell's latest video documenting the construction process.

The smallest defect in the paint covering the 260,000 tonnes of steel used on Prelude could lead to disastrous consequences as the facility is exposed to the elements.

Prelude will be moored on the North West Shelf for 25 years before being given the chance to return to dry dock for maintenance. That's five times the usual period between drinks for a seafaring vessel.

Another big challenge for the construction and design crew is looking after the human capital onboard the unit, with seemingly trivial details making all the difference for personnel spending lengthy periods at sea.

At busy periods, some staff will need to share quarters, prompting designers to ensure that all amenities are even stevens, right down to the width of the mattresses.

When put into operation, Prelude is expected to produce 3.6 million tonnes per annum of LNG, 1.3MMtpa of condensate and 400,000tpa of liquefied petroleum gas for export.