The website warned that the need for such policies is particularly vital to the ten per cent of homes in the UK that are at risk of flooding.
Rachel Stiles, spokesperson for Fairinvestment.co.uk, said the findings were "quite a surprise".
"With so many homes at risk due to poor flood defences, home insurance really is a necessity that should not be forgone," she explained.
"Brits are having to watch their spending as the credit crunch continues to take its toll, but home contents and building insurance should not be compromised when flooding is such a real possibility in the UK."
Nationwide recently urged those affected by the recent floods to contact their insurers as soon as possible.
The building society also claimed that people should consider emergency repair work to limit the amount of damage caused to their property.
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