Is My Property at Risk?

Buying a House?

There are some specific lender requirements, specified in the Council for Mortgage Lender (CML) Guidelines, that you should be aware of:

  • The Conveyancer must carry out any searches that may be appropriate to the property; considering its locality and other features (including subsidence).
  • The property requires an insurance policy in place that includes provision for damage resulting from ‘subsidence, heave and landslip’.
  • There may be a defect that is not covered by the lender’s valuation report. It is recommended that the borrower should not rely on the valuation report alone, but should obtain more detailed reports on the condition and value of the property.

Previous Subsidence

If the property owner has previously submitted a subsidence claim, or has any knowledge that the property (or neighbouring properties) has suffered historically from subsidence, this must be disclosed to their conveyancer/solicitor.

A Valuation Surveyor inspecting a property on behalf of a lender is also required to confirm whether they have any knowledge of subsidence affecting the property or neighbouring dwellings.

Where there is a history of subsidence, the lender may request detailed reports with a view to:

  • Withdraw or not proceed with a mortgage offer
  • Caveat the offer subject to further investigations

In addition to the traditional National House Building Council (NHBC) Guarantees, when all subsidence repairs are completed there may be a Certificate of Structural Adequacy issued by the technical expert acting on behalf of the insurance company.

Home Owner?

Find out whether subsidence is a common problem in the immediate area and whether your property is built on clay soil. These two factors alone will be a good starting point for assessing your risk of subsidence.

Distribution of shrink/swell soil

Clay soil characteristics vary greatly; not only between regions but on a single site. London clay is generally the most shrinkable soil type, but other clay formations (and even silty soils) can be shrinkable.

The British Geological Survey publishes a map showing the distribution of postcodes most affected by shrink/swell clay across England and Wales.

Property Type

The type of property is less of a factor than the depth of the foundations and the proximity of trees and drainage systems.

Building regulations have evolved over time to reflect an increased understanding of the risks of subsidence. The main changes were introduced in 1976, where building foundations were required to be of a certain depth or constructed in such a way as to safeguard the property against damage by swelling, shrinking or freezing of the subsoil.

Conservatories are a higher risk, as they are usually built on shallow foundations that can move differentially against the deeper foundations of the main building.

Trees and Vegetation

Identify whether the property is within the zone of influence of surrounding trees.


Check that there are no blockages by lifting the manhole and inspecting the drainage system (please take care when doing so).

Alternatively, we provide a range of subsidence services to help you identify and manage the risk of subsidence.

CET Subsidence Support