Category: Climate perils · Reviewed by Chrissie Anderson, Client Executive · Last reviewed 2026-06-10
Subsidence insurance is the element of a UK buildings policy that responds to the downward movement of the ground beneath a building’s foundations, together with the related perils of heave (upward movement) and landslip (sideways movement), each subject to a high mandatory excess and specific claims-handling protocols.
Category: Climate perils Also known as: Subsidence cover, Ground movement insurance, Heave and landslip cover Typical UK market form: Named peril within domestic and commercial property all-risks, with high mandatory excess Related concepts: Property insurance, Buildings insurance, Flood insurance UK
Subsidence is the downward movement of ground supporting a building, generally caused by changes in the volume of underlying soils, the removal of subsurface material (for example by leaking drains or historic mineral extraction), or the action of nearby vegetation. Heave is the opposite phenomenon — upward movement of the ground, typically associated with the rehydration of shrinkable clay following removal of mature trees. Landslip is the downward movement of sloping ground.
The UK’s exposure to subsidence is dominated by the distribution of shrinkable clay soils across southern and eastern England — particularly London Clay, Gault Clay, Oxford Clay and Lias Clay. These soils undergo significant volume change in response to moisture deficit, making subsidence claims correlate strongly with hot, dry summers. The British Geological Survey publishes GeoClimate UKCP18 data products that map subsidence hazard across Great Britain under UK Climate Projections 2018 scenarios.
The British Geological Survey GeoClimate UKCP18 dataset combines BGS soil shrink-swell hazard maps with UKCP18 climate projections to forecast that the area of Great Britain at significant subsidence hazard from clay shrink-swell will expand materially through the 21st century, with the greatest increase under high-emissions pathways. The dataset is widely used by UK insurers, reinsurers and mortgage lenders in portfolio exposure analysis.
ABI quarterly weather claims data has historically recorded subsidence claim spikes following extended dry periods — notably the long, dry summers of 1976, 2003, 2018 and 2022. The Met Office’s State of the UK Climate report (Kendon et al, 2024) confirms that the United Kingdom is continuing to experience a higher frequency of hot and dry summers consistent with UKCP18 projections, with the 19 July 2022 record of 40.3°C at Coningsby weather station representing the first occasion that 40°C had been exceeded at a UK station.
Subsidence, heave and landslip are standard insured perils under UK household buildings policies and the majority of commercial property all-risks wordings. They are typically subject to a mandatory minimum excess of £1,000 per claim (often higher), reflecting the long claim duration and high investigation cost relative to the average building loss. Cover is restricted to physical damage to insured property and does not extend to merely cosmetic settlement, pre-existing structural movement, defective design or workmanship, or movement caused by alterations and extensions undertaken without proper foundation design.
The claim handling protocol established by the ABI Domestic Subsidence Agreement (between insurers of adjoining or successive policies) governs which insurer responds to a complex subsidence claim where damage develops over time and across insurer renewals. The protocol promotes a single-insurer point of contact for the policyholder and an equitable allocation of cost between successive insurers based on the period of cover during which damage occurred.
Commercial cover follows the same broad approach, with additional exclusions in respect of structures specifically designed to undergo movement (for example bridges, retaining walls and silos), and with property-specific subsidence excesses applied where engineering survey identifies elevated risk. Mining subsidence in the former coalfield areas of England, Scotland and Wales is dealt with under a separate statutory regime administered by the Coal Authority and is excluded from standard insurance.
The Coal Mining Subsidence Act 1991 places primary responsibility for coal-mining subsidence damage on the Coal Authority, with associated rights of remedial action and compensation. The Mines (Working Facilities and Support) Act 1966 and the Coal Industry Act 1994 provide further regulatory context. The ABI Domestic Subsidence Agreement, periodically updated, is the principal market protocol for handling cross-renewal subsidence claims.
The Building Regulations 2010 (as amended) and the relevant British Standards (notably BS 5837 on trees in relation to design, demolition and construction, and BS 8004 on foundations) set the design standards that determine whether new construction is considered to have been designed adequately for the underlying ground conditions. Insurers will typically refuse cover or apply specific exclusions where retrofitted alterations have been undertaken in breach of these standards, and may require an arboricultural management plan where significant trees are present near a structure on clay soils.
Commercial property occupiers and landlords in southern and eastern England should assume that subsidence risk will materially increase through the policy lifetime of any long-term lease or finance arrangement. Brokers should obtain BGS GeoClimate UKCP18 exposure information at survey stage for sites on shrinkable clays, request information on any historic subsidence claims, and review tree management plans. For larger commercial portfolios, accumulation analysis against the BGS subsidence hazard maps is increasingly expected by insurers.
Where extensions, conservatories or basements are added to existing structures, brokers should remind clients that proper foundation design and notification to insurers are essential, since retrofitted construction is a frequent root cause of subsequent subsidence claims.
Following the long dry summer of 2022 — which included the 40.3°C Coningsby record on 19 July 2022 — the ABI reported a marked uplift in domestic subsidence claim notifications, in line with the established correlation between extended moisture deficit on shrinkable clays and subsequent claim emergence across the autumn and winter months. The pattern has been observed in successive dry-summer years and is consistent with UKCP18 projections.
This entry is part of the Apex Insurance Wiki. Last reviewed by Matt Bartlett on 2026-06-10. Next review: 2026-12-10.
Apex Insurance Brokers Limited. Authorised and regulated by the Financial Conduct Authority, FRN 724952. Registered in England and Wales, Companies House 07014570. This entry provides general information about UK insurance concepts and is not regulated advice. Consult your insurance broker on your specific position.
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