Following a freezing winter, memorably featuring the month-long ‘beast from the east’, the UK’s summer of 2018 was the joint hottest on record according to the Met Office. For a six-week period between June and August day time temperatures regularly topped 30 degrees Centigrade.
For some sectors, such as tourism, warm temperatures are a welcome change. But for home and property owners, construction companies and many businesses, the sunshine can unexpected issues, such as subsidence.
With extreme weather predicted to continue as the effects of climate change set in, what can be done to minimise the impact to buildings?
The threat of subsidence
Subsidence has the potential to be a big problem for anyone who owns or maintains a building, whether domestic or for business.
If your building has subsidence it can be very expensive to resolve. Whilst ignoring the problem could lead to the value of a house or office going down or the emergence of dangerous structural issues for families, tenants or employees.
Subsidence occurs when dangerously dry soil conditions result in a sudden sinking of earth.
It is particularly problematic for buildings built on clay and near trees, with the loss of moisture in the soil causing the earth to dry and shrink. This can even lead to movement in the building foundations causing cracks and structural damage.
The issue is common in London where not only are buildings built on clay, but the city also generates its own microclimate, known as the Urban Heath Island (UHI) which often results in the centre of the capital being up to 10C warmer than rural areas, aggravating the effects of a heatwave.
According to one report, UK subsidence claims have gone up by more than 350 per cent in the summer of 2018. This follows a subsidence surge in 2003 which saw 54,100 insurance claims.
The Times reported on the issue in August 2018, claiming that the heat had also led to sunken driveways and decking, fallen ponds, shifting walls and cracks in plaster – with insurers bracing themselves for a rise in claims. 
It also referenced that the Met Office’s MORECS scale, which measures soil moisture deficit, was heading towards ‘high risk territory’.
Whilst subsidence is generally included within building insurance policies there is usually a higher excess. If the building is in a high risk territory, or there has been a previous subsidence claim, it is likely the insurers may charge a higher premium or refuse cover entirely. If your insurance provider is concerned about the risk of subsidence they might insist on seeing a report from a Chartered Structural Engineer before agreeing to insurance cover.
You may consider underpinning your property; by strengthening the foundations underneath, the risk of subsidence is reduced and there is more likelihood of being insured. Conversely, to partially-underpin the property could incur further issues later down the line; reinforcing one problem area could weaken the rest of the property.
How can you spot and mitigate building problems caused by extreme weather?
House and building owners are being advised to be more vigilant in future and inform their insurance provider as soon as possible when they spot signs of subsidence or any hot / cold weather related damage. These include bubbling in wallpaper (not caused by damp), cracks in walls and sinking patios.
Is this a sign of permanent climate change?
A Met Office spokesman said: “The heatwave and lack of rainfall we experienced in summer 2018 were part of natural cycles in the weather which cause temperatures to be elevated far higher than normal. However, the risk of heatwaves is increasing due to greenhouse gas emissions.
“Since the industrial revolution, global temperatures have risen by about 1C, meaning that temperatures experienced in 2018’s heatwave were higher than they would be without the additional effects of global warming.”
The bottom line is that hot summers and wet winters are becoming an increasing threat to buildings in the UK. If you are concerned about the risk to a property you own or manage then seek impartial advice from your insurance broker to find out how you can mitigate the risk in the most effective way.