Tuesday 6 January 2009

Subsidence Causes Risks and Prevention

Subsidence, in regards to housing, is when a building’s foundations begin to sink due to ground movement. Consequently and over time, this can cause significant cosmetic and structural damage to your home, but it can also be covered by suitable home insurance policies.

There are several causes for subsidence when it comes to typical residential areas. Surprisingly, about three quarters of subsidence claims are made from homeowners whose houses are built on clay, hence soil type can make an important difference when it comes to the likelihood of subsidence occurring, as an example clay contracts in very warm weather and expands when moist.

Vegetation can also be a problem. Tree roots draw moisture from the soil, again, causing shrinkage especially during warm weather. Similarly, damaged underground drains can also be a cause of subsidence often due to erosion underneath the surface of your home.

Homes that are at most risk are in areas where a high proportion of underground soil is clay-based. Geographically, this is most likely to be in the South East, including Norfolk, London, Kent, and the South. Statistically, subsidence occurs in one in 50 homes in London and the rate has increased as summers have got hotter and drier.

One of the most logical ways to prevent subsidence on your home is to frequently cut back any trees in your garden. Similarly, if you plan to plant any more, they should generally be the same distance from your home as they are in height. It is also important to be aware of the thirstiness of your trees, for instance, Elms and Willows soak up far more water than evergreens.

At this point, it is important to acknowledge that any crack that appears in your plaster or paintwork may not be due to subsidence. Over time, buildings move naturally because of their own weight and what is contained within. It is best to seek advice if cracks are more than a millimetre thick and begin to appear diagonally in weak areas, but purely cosmetic hair-lines are easy to fix yourself.

Specialists may be needed if heavy duty tree work needs to be done as consequences can sometimes be worse if a large tree is extracted completely. Also, there are certain rules for tree preservation in effect and it is best to research these before any major work needs to be done.