Hail smashed about 90 per cent of the glass on the north side of the rooftop greenhouses at the University of Calgary during the July 12 storm. ((Submitted by Derek McBurney))

A storm that pounded Calgary last month with almost four-centimetre-wide hailstones has smashed a national record for damage expenses, the Insurance Bureau of Canada said Wednesday.

The powerful hail that dented cars and damaged homes and businesses on July 12 resulted in about $400 million in insurance claims — a record amount for a hailstorm in Canada, the bureau said.

That tally surpassed the old record of $342 million set by another Calgary hailstorm in 1991.

Top 2 events for most insured damage

$1.6 billion: 1998 ice storm in Eastern Canada.

$500 million: 2005 rainstorm in Toronto that flooded basements and backed up sewers.

Source: Insurance Bureau of Canada

"There is no doubt that we are seeing more and more the impact of severe weather in Alberta," said bureau vice-president Doug Noble.

Insurance companies are working through about 60,000 claims. The $400-million estimate does not include damage to agricultural crops in the province.

Mark Armstrong, owner of the Dent Clinic in Calgary, said he's booking appointments into August of next year to fix hail damage to vehicles.

It is too early to gauge whether the storm will cause a spike in premiums, said insurance bureau director Robert Tremblay.

"There is a lot of factors that influence premiums. It all depends on what kind of exposure each company had in that specific market," he said.

"But one thing for sure is that we are having more and more extreme weather events, not only out West, but we also had quite a few events in the East."

With files from The Canadian Press