SUBSIDENCE ISSUES DUE TO MINING

Written by

Emma Myrie

Insurance Underwriting Expert

Reviewed by

David Joyson

Home Insurance Expert & Customer Champion

Mining subsidence occurs when the earth beneath or near a property’s foundations has been weakened or hollowed out by mining works. This causes the downward movement of the ground upon which a building sits.

Access to disused mine sharts is generally blocked off by ‘mine caps’, but these can give way after years of decay, as they are often only made of timber and were never designed to hold up as long as they usually have.

Some mine shafts may were abandoned as long as 150 years ago, so it is possible that no record of them was ever made. Because of this, homeowners could live on top of a disused mine shaft for decades without ever being aware that it is there (though this might be favourable, as ignorance is bliss in terms of mining subsidence). Mining works that travel directly beneath a building’s foundations can cause catastrophic damage in the event of collapse, which could dramatically affect your home insurance.

Knowing the history of mining in the area

When buying a home in an area that has a known history of mining, one of the first checks that you should carry out before exchanging contracts is a Mine Search Report or an Archival Mining Report.

If you are employing a solicitor or Chartered Surveyor they should carry out these checks on your behalf, but it is worth making sure that they are done. The reports use archived data in the public domain and often in private records that illustrate potential risks from old mining works. They are relatively cheap to obtain, considering the staggering costs if you encounter a subsidence problem down the line. Estimates show that between 20%-30% of the mining reports undertaken will reveal a potential hazard.

Problems revealed

If a problem is revealed, such as a mineshaft running directly beneath a house, then it is vital that investigative work is carried out before you agree to buy a home. This site investigation process can be expensive, time consuming and occasionally disruptive to occupants.

Often a drilling investigation will be required, to establish whether a house stands on solid bedrock and not over one that has been partly removed by mining. Several bore-holes are made at various points around the property, reaching to such a depth that a firm footing can be reached. Though the process can be expensive, it’s still carrying out because it’s a small price to pay compared with your expenditure on buying a home.

Depreciation and compensation

Different areas might be affected by different types of mining. The Coal Authority advises that coal mining, both historical and recent, has been carried out in various locations across the UK. Coal mining locations might be found spread from South Scotland, through Northern England, crossing down to the Midlands, then into the South West as well as Southern and North Western Wales. Under the Coal Mining Subsidence Act 1991, homeowners affected by subsidence caused by coal workings may be entitled to remedies such as depreciation compensation payments and repair works.