Amphibious architecture allows an otherwise-ordinary structure to float on the surface of rising floodwater. An amphibious foundation retains a home’s connection to the ground by resting firmly on the earth under usual circumstances, but allows a house to float when flooding occurs.
A buoyant foundation is specifically designed to be retrofitted to an existing house that is already slightly elevated off the ground and supported on short piers. Under the house the foundation’s buoyancy blocks provide flotation, vertical guideposts prevent the house from floating away, and a frame ties everything together. Any house that can be elevated can be made amphibious.
Amphibious retrofitting has not yet gained widespread acceptance, and buildings with amphibious foundations are not eligible for subsidized policies offered by the National Flood Insurance Program.