UK's first amphibious house becomes a "free-floating pontoon”

For the first time in the UK an "amphibious" home has been granted full planning permission and is set to be built on the banks of the River Thames in Buckinghamshire. The residential home designed by Baca Architects is an architectural feat that overcomes the threat of flooding by becoming a "free-floating pontoon" during a flood situation. "In an extreme flood, a 1 in 100 year event, the house can rise over 2.5 meters [8.2 feet]," Richard Coutts, director of Baca Architects told Gizmag.

This technology presents a major breakthrough for British architects who for some time have been investigating ways to mitigate the risk to homes located in flood-prone zones. The modern 225 sq m (2421 sq ft) home will be set just 10 meters (32.8 ft) from the river's edge, replacing the current dilapidated bungalow that sits in a Flood Zone 3b (classified as the Functional Floodplain). "Options for the site included either a floating or an elevated property," explained Coutts. "An elevated building would be set high enough to avoid an extreme flood but has the disadvantage of being almost a storey away from the garden. An amphibious house solves these issues by allowing occupants to enjoy their garden and only rising to avoid floods when necessary."

While the amphibious house will rest on the ground on fixed foundations, during a flood situation the entire building is designed to rise up in its dock and float there, remaining buoyed by the flood waters. This is possible due to a wet dock, comprised of retaining walls and base slab, that sits underneath the home. When flooding occurs the dock fills with water and the house rises accordingly. To prevent the house from simply floating away, four dolphins (permanent vertical posts) are arranged close to the sidewalls.

The home is designed to be a highly-insulated and low energy building, featuring water saving and energy saving devices, large windows, pitched roofs and a chimney to complement the irregular roof-line of neighbouring homes. The glazed south facing facade offers panoramic views towards the river that also overlooks a well designed riverside garden that is both pretty and functional. Acting as a natural warning system, the garden, with terraces set at different levels, would flood incrementally thus giving the occupants enough warning to assess the situation and evacuate if necessary.

Only a handful of amphibious homes of this nature have been built around the world. "Similar properties have been built in Holland and New Orleans but this will be the first in the UK," said Coutts. The Dura Vermeer Group constructed 32 amphibious dwellings and 14 floating homes in Maasbommel in the Netherlands in 2005. These homes were also built using floating bases that were anchored to mooring posts and they successfully performed as designed during the Dutch floods of February 2011.

Building an amphibious home currently costs around 20% to 25% more than a similar sized house - perhaps a price worth paying for the premium waterfront location and peace of mind?

Baca Architects established the Life project (Long-term Initiatives for Flood-risk Environments) in 2005 to identify ways in which the construction industry could help to tackle rising carbon dioxide emissions and adapt to climate change - and in particular to flood risk. The initiative seeks to promote new approaches that contribute towards the development of more holistic sustainable policy making in the future.

In the future Coutts foresees that large communities will be holistically planned to be better prepared for flooding and climate change. "Dwellings will be low carbon, and organized around multifunctional landscapes that will help control surface water flooding or act a large flood storage areas," said Coutts. "New communities will be made up of streets of flood resilient dwellings located on the highest ground with amphibious homes located in the transitional zones between development and the natural environment."

Sources: Baca Architects, Life Project