Hundreds of thousands of homeowners will be hit with higher household insurance premiums as a second wave of flash floods gives insurers their biggest ever claims bill.

As a summer of appalling weather brought another day of travel chaos yesterday, analysts said that household insurance rates were expected to rise sharply for the first time in more than a decade.

The torrential downpours and floods across the country left many roads and railways too treacherous for travel. Severe conditions caused disruption and cancellations on train services throughout Wales, the South West and southern England.

During the worst of the weather, 141 flights were cancelled at Heathrow and flooding closed 25 Tube stations in London.

A combination of higher claims costs and frustration at government failure to strengthen flood defences were blamed for the expected rise in premiums.

Competition in the general insurance industry has kept rates steady for the past 13 years, despite the wettest autumn since records began in 2000 and the 80mph winds that caused widespread damage last year.

This weekend’s flooding could easily take the cost of claims past the £2.5 billion mark this month, according to leading analysts.

Fierce backroom lobbying from the industry helped to prompt the Government to promise that spending on flood defences would go up to £800 million by 2011.

However, the industry has been given no precise assurances on spending before that and is said to be increasingly frustrated. Analysts predict that it will introduce premium increases by stealth as high as double the rate of inflation.