THE building of Sunseeker's luxury 131 superyacht was charted in a documentary shown yesterday.

The Poole-based company allowed the BBC behind the scenes of its production line to film 'Britain's Biggest Superyachts', following the building of the state-of-the-art high-spec yacht through to its launch.

In fact the boat's construction was the most bespoke in the firm's history, with a high percentage of its 120,000 components specified by its anonymous US-based buyer.

Among them were a jacuzzi with pop-up fountains and LED lit cup holders, and a water wall in the bar area.

The build team faced many challenges during the construction, which ended with the launch of the vessel in January this year.

At one part of the programme, viewers were told that the client had objected to the type of marble used in the guest bathrooms, where the grain was deemed too prominent. Fortunately for the builders, who faced a big task replacing the stone at a cost of around £100,000, the client was eventually persuaded to stick with the original.

The documentary, which was shown on BBC Two at 9pm, involved ten months of filming.

Viewers heard how the firm has deliberately switched to targeting the super rich since the financial crash, as with banks and other lenders unwilling to back luxury purchases had caused the market for smaller and medium-sized yachts to dry up, putting the company in the red.

However, the firm's sales manager Mark Chinery said they could build four of the massive yachts a year, each worth at least £20 million, bringing in as much cash as 40 small or mid-sized vessels.

The programme also heard from the company's founder, Robert Braithwaite, who said he personally felt much more at home walking his dog or going to the pub than on a superyacht.

He also said: "You can come up with the idea to build this business, but unless you have a good team you don't go anywhere."

The millionaire, who recently funded a surgical robot for Poole Hospital, has sold his shares in the firm but still visits the factory floor, where nine boats are under construction at all times.

The firm employs more than 2,000 people, taking on 30 apprentices each year.

The 40m 131 yacht was the largest model ever to make its debut in London.

The programme concluded by saying the firm has five new superyachts already on order.

Sunseeker announced in January this year that it would be hiring 225 skilled staff in Dorset rather than the previously announced 100.

It said it was looking at a “very strong” order book for 2016, boosted by plans for several new models.

The company said last year that it had made a loss of £41million in 2014 but said it expected to return to profit in 2016. Its 131 Yacht, revealed last autumn, is the first of three models set for launch this year.