Go with the float: This pioneering amphibious home from 'Grand Designs' is for sale

If I asked you to name something that floats, what would spring to mind? A boat? A paddle board, perhaps? But a house? No, me neither. Yet Formosa is exactly that: a house that floats. In fact, it is believed to be the UK’s first amphibious house.

This innovative home sits on Lock Island in the River Thames in the upmarket Buckinghamshire town of Marlow. On a normal day, Formosa rests firmly on the ground. But during a flood, it rises in its own wet dock and floats.

It’s no wonder this ambitious project caught the eye of Channel 4's Grand Designs. Presenter Kevin McCloud followed Andy and Nicki Bruce’s journey to build their flood-proof home in an episode that hit screens in 2014.

The Bruces had always dreamed of living by the river, but the steep house prices along the Thames made it difficult. So, they bought a riverside plot on Lock Island, knocked down the rundown bungalow that sat on the land, and set about building a new home from scratch.

But this was no mean feat. For starters, the flood-proof design was brand new to the UK. The island itself presented a logistical headache too: it can only be reached via a footbridge. The solution? A 46-year-old NATO pontoon from Holland — complete with an instruction manual in German. This was transformed into a chain ferry to shuttle equipment and materials between the mainland and the island.

It was, at times, a rocky road. In McCloud’s words, the couple were ‘beset with misfortune and logistical adversity like no other project I can remember’. And that’s quite something coming from McCloud, who has fronted the popular TV show since 1999.

But Andy and Nicki got there in the end. You’ve got to admire their ambition and tenacity. The question is, does this gutsy design actually stand up to the test? The answer appears to be a resounding ‘yes’. During flooding in 2019-20, the house ‘rose and fell exactly as intended, a quiet triumph of design over disaster’, according to Baca Architects, which designed Formosa, which is now on the market for £2,500,000 via Hamptons.

Putting the flood-proof design to one side, Formosa has impressive green credentials too. According to Hamptons, these include high levels of insulation, low energy systems, high-performance windows and a biodigester drainage system.

The house is a contemporary beauty in a market town that's brimming with historic buildings. It is all clean lines and vast slabs of glass, including an entire wall of floor-to-ceiling bifold doors. After all, with a riverbank setting like that, why wouldn’t you?

The interiors are understated, with engineered wood floors and neutral-coloured walls and cupboards, allowing the river views to take centre stage, says Hamptons. The three-storey house has a slightly topsy-turvy layout, designed to make the most of the setting.

The ground floor comprises two bedrooms (one with an ensuite) at the front of the house and a large living space, incorporating the kitchen as well as dining and sitting areas, at the back. This light and bright part of the home offers stunning views of the river.

On the lower ground floor, there’s a rather versatile-sounding ‘cinema/games room/bedroom’, a utility room, another bedroom and a bathroom. Meanwhile, the whole of the first floor is dedicated to the main bedroom, complete with a dressing room and a bathroom featuring a sauna and steam room.

Outside, the garden steps down to the river, where there’s a private mooring. And a pergola acts as a ‘virtual’ room. Andy says: ‘We love living on the River Thames in Marlow. Eleven years ago, we were given the opportunity to build something really special, and Formosa is just that. You might recognise it as the “amphibious house” from Grand Designs. It allows us to live right on the river without any risk of flooding. It’s given us the most peaceful spot and beautiful family home, yet it's just a 400-metre stroll into Marlow High Street.’

Charles Wellbelove, an associate director at Hamptons, adds: ‘Built on a specially engineered hull and joists, [Formosa] offers the reassurance of waterside living without the concerns that typically accompany it.

‘Beyond its remarkable design credentials, Formosa enjoys an exceptional setting on a private island community and is just a short walk from the popular town of Marlow. I have sold many beautiful riverside homes over the years but never one that floats!’

Formosa is for sale via Hamptons — see more details here.