Interactive subsidence map shows how it affects your area

Home insurance premiums are set to rise on a spate of claims as insurers report paying out £219m last year – £9,600 per home.

Subsidence is where the earth sinks under a house, which can cause property damage.

It is normally caused by warm weather, where the soil dries out, as happened in the UK last year with the late summer heat wave.

Insurers now think their bill for subsidence claims will reach £219m by 2022, the highest level since 2006.

Last summer’s heat wave led to 18,000 subsidence claims – the equivalent of one new claim every 15 minutes in the second half of last year.

Last summer’s record-breaking heatwave has led to an increase in claims payouts this week, according to figures from the Association of British Insurers (ABI).

The heatwave – which peaked with the highest UK temperature since records began at 40.3 degrees on July 19 – resulted in the equivalent of one new subsidence claim being made every 15 minutes in the second half of the year.

Insurers expect to pay £219 million in claims by 2022, many of which were triggered by last summer’s record-breaking high temperatures.

This is the highest expected subsidence bill since 2006, though insurers are still working out the exact total.

Of the 23,000 subsidence claims filed during the year, the majority – 18,000 – occurred in the second half of the year after the summer heat wave.

The ABI previously warned that home insurance premiums could rise this year due to a spike in subsidence claims.

The good news is that home insurance prices are currently at an all-time low.

But the bad news is that these costs are likely to rise in 2023, as insurers pass on the cost of frozen pipe claims, rising material and labor costs, and subsidence claims.

ABI General Insurance Manager Laura Hughes said: ‘Thousands of homeowners felt the impact of last summer’s record-breaking heat wave long after temperatures returned to normal.

‘Insurers understand that subsidence is worrisome and stressful. They have, and will continue to support their customers during each monitoring period to determine the extent of the damage and what repairs or work is required for a long-term solution.”

According to Geobear’s CEO, Otso Lahtinen, subsidence in the UK is on the rise.

Lahtinen said the historical norm for subsidence is one bad “event year” in seven.

But there have been two event years in the last five years alone, he said.

The risk is especially in areas with clay soil. The Southeast region has clay that is particularly reactive to heat.

Some buildings are also more at risk of subsidence than others. Victorian terraced houses with shallow foundations, especially on clay soils and near large trees, are particularly susceptible to subsidence.

While insurance contracts normally cover subsidence costs, this may only be the case once per property.

Helen Phipps, home insurance comparison expert at Comparethemarket, said: ‘Sag cover is typically only included in most property insurance policies if the property has never suffered from it before, so you should never assume you’re automatically covered. Insurance costs may vary depending on building type, as well as proximity to trees and/or water.’

How to deal with prolapse

Subsidence should be something that is covered by your home insurance. This means that apart from the deductible, you should be able to avoid the cost of fixing it.

In some cases substantiation will be required. This is when additional support is added under a building to prevent it from sinking into the ground.

Careful Check: A good surveyor should notice problems outside the property, as well as within its walls

It is an expensive undertaking and the cost varies depending on the method used, the location, the size of the area, the type of property and whether the building is on a slope.

Average foundation costs are between £1,500 and £2,600 per m2, according to Checkatrade.

There are also a number of additional costs that must be factored in on top of the work itself.

If you live in a detached or semi-detached house, it is sometimes necessary for an appraiser to make party wall agreements between you and your neighbours.

Before starting work, notify and pay your local building control agency. The costs will vary per municipality.

You may also need an architectural surveyor, a contractor, or a tree surgeon.

In our reader’s case, since they have to take down the entire extension and start over, it costs quite a bit more.

The average cost for a 20m2 extension is £37,500, according to Cheackatrade – and that doesn’t include the demolition and removal of the original extension.