Half of all homeowners with foliage-filled gardens are blissfully unaware of the damage that tree or plant roots can cause to their homes, according to a survey carried out by NOP, on behalf of Halifax General Insurance.

Alarmingly, 50% of the 1,000 adults questioned also had no idea that they may have to pay the first £1,000 of any insurance claim due to subsidence, even though 72% of those with a private garden had planted trees or shrubs in them at some time.

Although 71% of those who had planted foliage claimed to have thought about the distance of the trees or plants from the house, many far under-estimated the safe distance for planting certain types of trees from their homes.

• Two-thirds under-estimated the safe distance for planting a willow tree.
• Almost half under-estimated the safe distance for an oak tree.
• Four in ten under-estimated the safe distance for a hawthorn tree.

Four in ten of those questioned thought that mortgage providers would lend them money on a property that had suffered from subsidence in the past, but only 15% said that they would consider buying a property that had previously suffered from subsidence.

Watch out for willow and poplar

According to advice from The Tree Council, it is very important to consider the proximity of trees to your home and other structures, especially species such as willow and poplar. These types of species have a larger requirement for water than other trees, and therefore are more likely to cause problems as a result of ground shrinkage due to the extraction of water.

They stress that it is also important to remember that the likely range of a mature broadleaved tree's root may often equate to twice the ultimate height of the tree.

According to statistics from the Association of British Insurers (ABI), there are certain distances that should be maintained when planting trees near buildings. However, it is important to note that these distances are only a rough guide, and the distances which trees are planted from a building mainly depends on the type of soil in which they are planted.

Howard Posner, managing director of Halifax General Insurance, said:

"While buildings insurance covers many eventualities, it is still important to remember that subsidence can prove very distressing and inconvenient to the homeowner.”

"Gardening and home improvement programmes have encouraged many homeowners into DIY landscaping and planting, and while this is to be applauded we are simply issuing a word of caution about trees in particular.”

"People looking to buy a home should give careful consideration to its garden, not to mention the neighbouring land. And homeowners looking to plant trees should remember the safe tree planting distances - a small sapling may not look like a potential hazard now, but once grown it can become a real problem.”

"As the saying goes, ‘from small acorns do mighty oaks grow.’"

Meanwhile, scientists have begun using a DNA technique to identify trees that could cause subsidence damage to homes, in so-doing helping subsidence disputes. Marishal Thompson, backed by a group of Newcastle University scientists, are believed to be leaders in performing this type of testing.

When two similar trees are growing in the same area, it is often difficult to tell which tree is causing structural damage, as the roots of each can spread a long way, in several different directions. The so-called 'fingerprinting' check can be used to help settle both neighbourly disagreements and potentially assist insurance companies settle claims.

Buildings insurance is available to all home owners and all good policies provide subsidence cover. However most include £1000 subsidence excess. In most instances the insurer will appoint an expert to oversee the repairs to the home. At Halifax these experts are employed in-house to give maximum service to customers

For more information contact Halifax General Insurance on 0800 028 2498, or visit www.halifax.co.uk/insurance

This list is not exhaustive and should be regarded as a gide only. Source: ABI

NOP Survey Results: