Figures released by Abbey Home Insurance showed that underinsurance results in 257,000 claims being declined each year, because of the policyholder not having the appropriate home insurance cover.
Mr Shrastri said the issue highlights the problem of people purchasing insurance policies "based solely on price", as opposed a policy that would provide effective cover.
When flooding is expected, Mr Shrastri recommended people to "protect belongings by moving them upstairs", using "sandbags to prevent water entering the home" and to make sure that the house has "both contents and buildings cover".
Among the worst hit areas by the flooding, Edgbaston in Birmingham recorded 3.4 inches of rain in 24 hours on Friday and Saturday.
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