Cranfield National Perils Database

The source subsidence data is produced through the Natural Perils Directory™ (NPD) geohazard vulnerability datasets and associated report have been prepared by Cranfield University and covers England, Wales and Scotland. This unique data represents the most detailed available information for any kind of soil-related vulnerability assessment. The subsidence peril includes a range of soil-related models together with 15 associated climatic scenarios.

Subsidence damage is the result of ground movement at and around foundation depth. The kinds of soil effects directly associated with ground movement include:

Clays – shrinkage and swelling of clays, known as clay-related subsidence;
Sands - sandy soils susceptible to sub-surface erosion, causing sand-related subsidence;
Silts - silty soils associated with heave under frosty conditions causing silt-related subsidence;
Soft soils - soft (alluvial and peat) soils being compressible and susceptible to soft soil-related subsidence;
Peats - peat, which shrinks considerably on drying causing peat-related subsidence.

Of these, it is universally accepted that clay-related movement caused from shrink-swell is by far the most extensive cause of soil-related subsidence in Great Britain and together with the other soil related hazards represents approximately 70-80% of soil subsidence cases. NPD provides a detailed and informed assessment of the location of clays prone to shrinkage across Great Britain.

Because clay related soil shrinkage and swelling is the most common form of subsidence in the UK it is this effect of ground movement that NPD focuses on and which we have built into Addresscloud.