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Subsidence: what every home owner needs to know

Subsidence: what every home owner needs to know

Do you ever get that sinking feeling that at any moment something is about to go terribly wrong? Well that rumbling in the pit of your stomach may have less to with the stress of a new promotion and more to do with the sickly state of your house’s foundation.

In Sarah Beeny’s property programme Help My House is Falling Down scores of couples were flabbergasted to find that their houses had a distinctly dodgy side on view.

The homeowners were also left wide eyed as mini-models of their homes were used to show what could happen if the subsidence on their homes continued at its present rate. Invariably the experiments saw side walls crumbling into oblivion, leaving homes at the mercy of the elements.

Subsidence, defined as “the downward movement of a building foundation caused by the loss of support of the site beneath the foundation” by the Institution of Structural Engineers and the Association of British Insurers, inspires fear in the majority of homeowners who have no idea of the impact that the structural classification will have on their homes.

Subsidence affects around 40,000 homes a year, particularly in the southeast, and if you feel that your house may be on a downward slope, you should take heed of the following Q & A guide to the blight of building foundations.

Will my ability to get insurance be affected?

The short answer is no according to the view from Jim Lincoln, Household Underwriter at Norwich Union. He argued that insurers will still back homes who have reported continued subsidence, and that they won’t put a levy on buildings insurance premiums.

However, this is all dependent on home owners acting quickly to report and address the problems as they arise. Scrutinise your policy for further details.

Will my home be devalued?

Subsidence may not hamper your sale, as you may be able to negotiate a lower price with purchasers to compensate for the problem. If the problem has already been attended to its critical that you have a Certificate of Structural Adequacy to demonstrate this.

Are mortgages available for houses with subsidence?

As long as the right paperwork is in place, such as the certificate above, and the problem of subsidence has been dealt with this shouldn’t be a barrier to getting a mortgage.

Can I do anything to prevent subsidence?

Unfortunately there may be little that homeowners can do to prevent the problem. However, completing a structural survey on your new home will highlight the problem.

How does it happen?

Trees are at fault for 65% of cases, particularly those that are planted in clay soils at too close a proximity to the house. A further 25% are caused by leaking drains and water mains, which act to soften the ground beneath a house and in some cases actually wash it away.

How can I tell if my house has subsidence?

The main indicator of subsidence is cracks, but not all cracks can be attributed to the condition. Cracks wider than 2mm could have formed as a result of subsidence. Ask a structural surveyor to look over any suspected cracks.


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Published 6 March 2012