Climate Change and Subsidence: Understanding the Risks and Taking Action

According to recent figures released by the Association for British Insurers (ABI), insurers paid out £585 million for weather-related damage to homes and possessions in 2024.

This is a record high for the UK, which has had to contend with consistent and prolonged periods of extreme weather and floods.

This data offers local authorities a stark reminder of the urgency at which climate resilience measures are needed to protect our communities.

According to Mainmark UK, leading ground engineering company, a wider awareness of subsidence in homes falls under these climate measures needed.

Subsidence is when the ground beneath a property sinks, causing cracks in the brickwork and compromising its safety.

It is now considered a considerable climate risk for homeowners, with more wet and warm summers predicted. In London alone, it’s estimated that 40 per cent of homes could be affected by subsidence by 2030, due to the dense population and soft clay foundations.

Understanding Subsidence and its Causes

Subsidence can occur due to various factors, including changes in soil conditions, tree roots, and extreme weather events. As the climate continues to change, the risk of subsidence is expected to increase, making it essential for homeowners and local authorities to take proactive measures to mitigate its effects.

Climate Conditions that Increase the Risk of Subsidence

What climate conditions increase the risk of subsidence?

Freya Chapman, Residential Lead for Mainmark UK, said: “In recent years, surges in subsidence have been attributed to prolonged periods of heat, which dries out and shrinks the soil beneath our homes. When this happens, the foundations can shift, and properties can become vulnerable to movement.

“Floods and storms can also cause subsidence by washing out the fines and creating micro-voids. If these get larger over time, our homes can sink down into these voids.

“The wider impact of subsidence for the public is huge – not least, potentially rendering our homes unsafe.

“If left untreated, subsidence is costly to fix and while some insurers might cover it in the first instance, an upward trend in these claims will cause premiums to rise. Homes with a high subsidence risk – generally those built in areas of soft clay soil and located near trees – may even be refused cover.

“So, as part of the Government’s Climate Resilience Review, there needs to be more engagement with industry experts on the prevention of climate disasters, including subsidence.”

Futureproofing our Communities

Futureproofing our communities

Futureproofing our communities is a priority for Mainmark, who through its involvement with key events like Grand Designs Live (for which it was the official subsidence partner in 2024), is working on educating the public on the common signs of subsidence.

These include cracks appearing in walls which grow larger over time, sinking floors and water pooling around a property. In very severe cases, subsidence can result in sinkholes – much like the one witnessed by the Godstone, Surrey, community in February 2025.

David Hedley, Commercial & Infrastructure Lead at Mainmark, said: “Sinkholes will occur when there has been damage to water mains or sewers, which has washed away the soil fines and created large voids underground.

“As bouts of extreme weather – from washouts to periods of draught – become more prominent with climate change, I would expect these to trigger more ground instability events in years to come. In the last year alone, sinkholes appeared in Wimbledon, Merthyr Tydfil and Nottinghamshire, resulting in disruption and costly repairs.”

Collaboration and Solution

Freya and David both believe that through industry associations like the Subsidence Forum Committee, which recruits housing developers, architects, arborists, geologists, insurers and subsidence experts, collaboration to solve these issues head on is very achievable.

Freya continued: “For every potential climate threat, collaboration between local government and industry experts will be the ultimate solution to futureproofing. The likelihood of damage to homes and infrastructure from floods, storms, and draughts will only worsen the longer these risks lie unaddressed.

“There has been a lot of progress in recent years to research and developing new, sustainable methods of soil testing, which will hopefully provide housing associations and developers with ‘concrete’ evidence on soil quality, depth and structural integrity ahead of any large-scale construction projects.

“If backed by a comprehensive Climate Resilience Review, we can protect the estimated 6.54 million homes which will be at medium to high risk of subsidence by 2030.”

About Mainmark UK

Mainmark UK, part of the Mainmark group of companies, was established in the UK in 2015. Hitting its milestone tenth anniversary this year, the company is aiming to further its innovative and efficient solutions to a wide array of ground engineering challenges, with Freya at the helm of its residential offering.

Conclusion

In conclusion, subsidence is a significant climate risk that affects many homeowners in the UK. As the climate continues to change, it is essential to take proactive measures to mitigate its effects. By understanding the causes of subsidence, futureproofing our communities, and collaborating with industry experts, we can protect our homes and infrastructure from the devastating effects of subsidence.

Frequently Asked Questions

What is subsidence?

Subsidence is when the ground beneath a property sinks, causing cracks in the brickwork and compromising its safety.

What causes subsidence?

Subsidence can occur due to various factors, including changes in soil conditions, tree roots, and extreme weather events.

How can I protect my home from subsidence?

You can protect your home from subsidence by being aware of the common signs of subsidence, such as cracks appearing in walls, sinking floors, and water pooling around the property. It is also essential to collaborate with local authorities and industry experts to futureproof your community.

What is the estimated number of homes at risk of subsidence by 2030?

According to Mainmark UK, an estimated 6.54 million homes will be at medium to high risk of subsidence by 2030.

What is the role of Mainmark UK in addressing subsidence?

Mainmark UK is a leading ground engineering company that provides innovative and efficient solutions to a wide array of ground engineering challenges. The company is working to educate the public on the common signs of subsidence and collaborating with industry experts to futureproof communities.