Insurers have received 4600 claims after the largest earthquake to ever strike Victoria took Australians by surprise last week, the Insurance Council of Australia (ICA) says.

No dollar estimate of insured losses is available yet, but the bulk of the claims are not significant structural issues and insurers have indicated they do not expect to incur major costs. ICA has not declared the event a catastrophe.

Home, commercial property and business interruption insurance policies generally cover damage caused by an earthquake.

While too early to accurately estimate potential costs, Suncorp CEO Steve Johnston said last week the quake was unlikely to trigger major cover and the insurer had received only a relatively small number of claims across its brands, including AAMI, Apia and GIO.

“We don’t expect it to be a big event from an insurance perspective but it’s a timely reminder of the value of the product we offer and the peace of mind it provides,” Mr Johnston said.

Early lodgements were made up almost entirely of home building claims in Victoria for minor damage such as fallen cornices and damage to plaster and render, ICA said after the quake, which struck around 9.15am on Wednesday, causing walls to shake and windows to rattle across metropolitan Melbourne and well beyond.

It measured 5.9 on the Richter scale, with the epicentre at Victoria’s Mansfield around 40km south of Mount Buller. The size of the quake, combined with the geology, means it was felt hundreds of kilometres away from the epicentre from Sydney to Hobart and west to Adelaide.

Buildings in Melbourne’s inner city were damaged and there were power outages and interruptions to public transport.

COVID restrictions may result in it taking longer than usual for commercial customers to identify damage as many buildings are unoccupied due to lockdowns and won’t be inspected as quickly as they otherwise would.

Allianz estimates the first 300 claims it received carry losses of about $5 million from a very wide geographical area, including SA and NSW, as well as Victoria.

Charles Taylor National Property Manager and Executive Adjuster Gary Pahl, who is based in Melbourne, said its building inspections have revealed some significant cracking, as well as frequent hairline, aesthetic cracking.

“Seasonal movement does result in cracking and we have to differentiate between that and new or more severe damage that is caused by this event,” Mr Pahl told insuranceNEWS.com.au, adding it was likely to be a long tail event.

“It certainly isn’t a Christchurch, it is nothing like that, but it was still a significant event.”

GeoScience Australia says the earthquake was the biggest to hit Victoria in “the modern instrumental era” since 1900, and probably since European settlement.

On average, Australia experiences an earthquake of this size once every year or two, Senior seismologist Hadi Ghasemi said.

“The Australian plate is the fastest moving continental land mass on Earth and is colliding into the Pacific plate to the north and east, and the Eurasian Plate to the northwest,” he said. Earthquakes are caused by the sudden release of this stress when rocks deep underground break and move along a fault line.

Wednesday’s earthquake occurred in Australia’s South-East Highlands region. Geoscience Australia received more than 40,000 reports from people reporting that they felt the earthquake, a record.

The closest seismic station to the earthquake was over 70 kilometres from the epicentre and Geoscience Australia has sent kits that will remain in the field for several months to measure seismic signals from aftershocks and is analysing satellite data to improve hazard estimates and to guide building design.

The 1989 Newcastle earthquake was magnitude 5.4 and about every ten years or so, Australia experiences a potentially damaging earthquake of magnitude 6 or more. The 1968 Meckering earthquake was magnitude 6.5 and the 1988 Tennant Creek earthquake was Australia’s biggest on record, at magnitude 6.6.