BRADFORD & Bingley have answered some common questions about subsidence. It is a real problem in the UK and is likely to affect thousands of homes this year, according to BBG Surveyors.

* What is subsidence?

It is a problem that develops when changes under ground cause foundations to shift and stop supporting the walls as they should.

* What causes it?

There are many reasons for a house to suffer subsidence. Some of the most common are:

1) clay soil under a home shrinks in the summer when dry and expands when wet causing the foundations to move.

2) Past mining in the area.

3) Extracting water from the ground for some commercial activity.

4) Other activities, such as tunnelling for drains.

* What does it look like?

The tell-tale signs of subsidence are usually cracks or bulges in the walls or floors of a building.

* How to check if you suspect subsidence?

Firstly, not all cracks mean subsidence problems. There are lots of other causes. For instance, cracks to plaster can be caused by vibrations from nearby construction work as in when building an extension to a house.

If you are concerned, take expert advice.

* Is it possible to check before one starts the house-buying process?

If you wish to make a start there are numerous websites available with investigation functions - www.home-envirosearch.com or www.homecheck.co.uk are two that can provide results by postcode.

* When a buyer has found the ideal house, what should they do?

It is always best to contact an expert for a thorough investigation, such as a surveyor. Before buying a home you should arrange for a building survey to be undertaken which will tell you if the house has a subsidence problem.

* What will happen if it turns out my house has subsided?

Don’t panic! Only in the rarest of circumstances will it need to be knocked down and rebuilt.

A loss adjuster, normally a qualified engineer, will be responsible for the ultimate decision as to what needs to be done.