Have you ever noticed unexplainable hairline cracks in your home, doors or windows sticking for no apparent reason, or rippling wallpaper that is not caused by damp, and thought nothing of it?
If you spot any of these problems and cannot find a reason for them, get specialist help as soon as possible. If it is subsidence, the sooner it is diagnosed the better. It is important to remember that subsidence can usually be rectified. Check that your building insurance covers subsidence and most insurers will aim to be as helpful as possible in dealing with any claim. They will recommend specialist advice.
A Chartered Surveyor will be able to work out whether or not there is subsidence and what the likely cause is. He may also need specialist geological and drain surveys. Moving soil can sometimes crack drains or water mains.
Establishing whether or not there is a problem can take a long time. There is rarely any cause for real concern unless cracks appear suddenly and are more than 3mm wide. In most cases, the first signs of a problem are visible cracks in particular areas of the house and these may need to be measured and monitored, perhaps for as long as 12 months. Solving subsidence can be a lengthy process which can take up to 2 years.
Underpinning the foundations usually prevents further movement. It is a lengthy, costly and disruptive procedure and can cost anywhere between £5,000 and £50,000 or more, and is used as a last resort.
Consumer champion ‘Which?’ estimates that 70% of all subsidence cases are due to tree roots sucking moisture out of the soil. Where this is the case, trees may be removed. It may be a quick and easy way to solve the problem.
More importantly, instead of solving the problem, removing a tree may add to it, but this is usually very rare. Your Chartered Surveyor will be able to put you in touch with someone who can advise you on whether or not a tree should be removed or simply pruned to reduce the amount of moisture it takes out of the soil.
Where the soil beneath the property is being washed away because of leaking drains or water mains, a less intrusive remedy might be possible. In most cases, repairs to the leaky pipework will be enough to stabilise the property without underpinning.
Check whether your insurance policy covers the cost of investigation and repair. If the loss adjuster/insurance company considers this reasonable, you will get your costs back. A policy excess will probably be specified in your insurance documents, in which case you will need to pay up to that amount before the costs are covered by the insurance. Your Chartered Surveyor will deal with your insurance company and help with any claim you need to make. They can also help design and arrange for any work needed to fix the problem. For more information visit www.rics.org/subsidence.