Sainsbury's warns that trees can be a major cause of subsidence

Almost 9.7 million people intend to plant at least one tree in their garden this year according to new research by Sainsbury's Home Insurance, but it warns that longer-term, these good intentions could lead to an increase in claims for subsidence. The Bank is urging the "green-fingered" among us to not only pick the most appropriate trees for the size of garden but to also ensure that any trees planted are an adequate distance away from our homes. For example, a maple tree should be planted at least 9 to 12 metres from your property.

Around 12% of the money paid out for subsidence by Sainsbury's Home Insurance is for claims caused by trees or other vegetation, and according to the Bank's analysis of industry data, UK insurers have paid out on average a staggering £710,000 a day for subsidence claims over the last five years, or nearly £5 million per week.

Neil Laird, Sainsbury's Home Insurance Manager said: "Planting trees is not only a commendable act in today's environmental climate; a well thought out garden can also add significant value to your property. However, people intending to plant a tree in their garden this year should be very careful about which type of tree they plant and how far away from the property they plant it. For example, our research shows that over 1.1 million people intend to plant a willow tree, which is a cause for concern given that this type of tree shouldn't really be planted any closer than 18 metres away from your property to avoid risk of subsidence damage.

"It's great news that so many of us are good-intentioned when it comes to planting trees, but it's important that we don't put our properties at unnecessary risk of subsidence. Our advice is to do your homework before putting spade to soil, seek some advice from your local garden centre."

Sainsbury's Home Insurance advises that there are a number of things people can do to reduce the risk of subsidence, such as:

Be careful which type of trees you plant in your garden and how far away you plant them from your property. Be particularly aware of popular ‘screens' such as Leylandii trees, which form very good garden dividers, yet grow very rapidly and are often planted too close to the property, posing a high subsidence risk.

If you have a smaller garden, consider planting Holly, Laurel or Magnolia trees which are all low water-demand trees and could be planted to within 5m of the property.

Check the survey for information on previous mining activity when you buy a property

Perform a survey on the drainage of your property

Perform regular checks for blocked or leaking drains, blocked gutters, and cracked pipes

Ensure that trees and shrubs are pruned regularly

If you suspect your property is suffering from subsidence, contact your insurer as soon as possible, as the sooner the problem is diagnosed, the sooner and easier it will be to repair

If your garden is too small to accommodate a tree, why not become a member of the Woodland Trust - on average, members paying £2.75 per month can help them protect and care for half an acre of native woodland - woodland-trust.org.uk

By far the most popular tree to be planted this year is the apple or pear tree, with more than one in 10 (11%) of British adults intending to plant at least one. This is followed by the cherry tree (7%) and the plum tree (4%).

On a location basis, those in the Midlands are the biggest tree planters, with 31% of adults intending to plant a tree in their garden this year, with those in the South East / East Anglia closely following with 29%.

The high percentage of people planning to plant trees in the South East will need to take particular care as properties in this region are among those most at risk due to the higher prevalence of clay-based soils which shrink as they dry out. Subsidence occurs when the ground beneath a property moves, causing the foundations and walls of a house to move and crack. Other causes of subsidence include abnormal flows of water through the ground from such things as leaking drains, or landslip on steep sloping sites. As global warming increases, the problem is expected to worsen.