Subsidence Insurance Claims Explained

What subsidence cover actually is

The subsidence section of a buildings policy covers damage to the insured buildings caused by movement of the site they stand on: downward movement (subsidence), upward swelling (heave, almost always clay rehydrating after a tree is removed) and sideways movement of sloping ground (landslip). Heave and landslip claims are rare; subsidence is the one that matters in London. "Buildings" normally means the house, an attached or detached garage, outbuildings and the walls, drives and paths within the boundary, which is why those items appear in the sum insured but, as you will see below, are treated differently when they are the only thing damaged.

Two boundaries define the cover. First, it applies to damage that occurs while the policy is in force, so where movement began under a previous insurer the two insurers may share the cost, a situation the Association of British Insurers handles through an agreement between its members. Second, it covers subsidence, not settlement. Settlement is the building compressing the ground under its own weight in its first years; insurers and the Financial Ombudsman generally treat movement within ten years of construction as settlement, and initial settlement should never produce more than hairline cracks. Subsidence is the ground itself losing volume or support because of something external: clay drying around tree roots, a leaking drain, a change in groundwater, an excavation next door. The test an engineer applies is whether the ground would have moved even if the house were not there. Our guide to the signs of subsidence covers how the two look different on the wall.

Three things the cover was never intended to do: pay for preventative underpinning where nothing has yet cracked; compensate you for any fall in the property's value, sometimes called blight; or repair the ordinary seasonal and thermal movement every building shows, the equivalent of a door that sticks in a damp month and frees itself in a dry one.

What is usually excluded

Policies differ, but these exclusions appear in most UK household wordings:

• Settlement and bedding-down, often defined as anything within ten years of construction, and settlement of made-up ground.
• Your own works. Damage caused by demolition, structural alterations or repairs to your own property, and damage from defective design, workmanship or materials. Damage caused by works to a neighbouring property may be covered.
• Ground-bearing floor slabs, unless the external walls are damaged by the same cause at the same time. Minor slab movement is rarely of structural consequence, and insurers know it.
• Paths, drives, patios, terraces, pools, garden and boundary walls, gates and fences, unless the main house, an outbuilding or a garage is damaged by the same cause at the same time.
• Coastal and river erosion, and chemical attack on the foundations.
• The excess, and anything above the sum insured where the property is under-insured.

The floor slab and garden wall exclusions surprise people most. A cracked patio next to a cracked wall is usually in; a cracked patio on its own is usually out.

What the policy expects of you

An insurance policy is a contract, and the conditions cut both ways. Four of them decide subsidence claims more often than the exclusions do.

• Notify promptly. Tell the insurer as soon as you see damage you suspect is movement. Delay lets the damage and the cost grow, and it can prejudice the insurer's right to recover its costs from whoever caused the problem, for example the owner of a tree. Late notification is a common reason for a reduced or refused claim.
• Maintain and mitigate. You are expected to keep your own trees managed and your own drains in repair, and to act on advice that a defect needs attention, whether or not the insurer has asked you to. Neglect can reduce what the insurer pays, or in a bad case defeat the claim.
• Disclose accurately. At renewal or when switching, insurers ask about subsidence, heave and landslip over a period, typically the last twenty-five years: claims made, signs of damage, monitoring, movement. Careless answers can void the policy; deliberate ones are a criminal matter. A survey comment that cracking is "historic" or "long-standing" is enough to prompt questions, so keep the engineer's report that explains it.
• Accept betterment where it applies. If you want a higher specification than the repair needs, or the damage is worse because the property was not maintained, the insurer can ask you to contribute.

The sum insured used to be a trap, because a property insured for less than its rebuilding cost could see its claim scaled down. Most household policies are now "factor-rated" on the postcode, bedrooms and construction type, with sums insured from several hundred thousand pounds to unlimited, so under-insurance is rarer than it was, but it is still worth checking the figure on the schedule.

How a subsidence claim runs

The sequence below is what a well-run domestic claim looks like. The timings are typical, not promises, and in a "surge year", when a hot dry summer produces more than 50,000 claims across the country, every stage slows down.

1. You notify the insurer. Photograph the cracks with a scale and a date first, then call. Check whether the policy is in joint names with your lender; it often is, though lenders rarely take part.
2. The insurer appoints its expert. Usually a loss adjuster, often a specialist subsidence firm, with an engineer or surveyor behind them. Their first visit is the initial appraisal: is the damage above the threshold that justifies investigation, is it foundation movement or something else, what is the likely mechanism, and can the cause be removed. For simple cases this is increasingly done by video with a technician on site. The insurer pays for this stage.
3. The claim is accepted or declined on the balance of probabilities. The expert does not need the exact cause at this point; a crack pattern consistent with ground movement plus a plausible external factor is normally enough to accept the claim, subject to the conditions being met. Declines at this stage are usually because the cracking is settlement, thermal movement or a superstructure defect such as a failed lintel or roof spread.
4. Investigation and monitoring. A full crack record, a level survey along the brick courses, crack monitoring from fixed studs read with a digital calliper, level readings every six to eight weeks, a CCTV drain survey with a water test, and trial pits with soil samples and root identification where trees are suspected. This is the stage that takes the time: six to twelve months is usual, and longer is common, because a summer and a winter are needed to tell seasonal clay movement from a leaking drain or soft ground. The insurer funds it.
5. Stabilising the cause. Where a drain is leaking it is repaired (our guide to leaking drains and subsidence explains how the leak is found and who pays for the pipe); where a tree is implicated an arboriculturist specifies crown reduction or, less often, removal, after checking for a preservation order. Monitoring continues through at least one more summer to prove the movement has stopped. Where the ground investigation shows a deep, persistent dry zone under a tree, removing it would lift the house, and underpinning with anti-heave measures becomes the remedy instead; our guide to trees on clay explains why.
6. The repair scheme. Once stable, the expert writes a specification and invites contractors to tender. In the great majority of cases that means crack stitching, repointing, rebuilding displaced brickwork, replastering and redecoration. In the minority it means underpinning, normally partial, with Building Regulations approval and possibly Party Wall notices. You can ask to use your own contractor, and a cash settlement for the agreed scope is sometimes offered instead.
7. Completion. The works are inspected, the defects period runs, the contractor's guarantee is issued, and the engineer signs a Certificate of Structural Adequacy. Keep every piece of paper from every stage.

Who pays for what

General practice under typical UK household policies; wordings and limits differ, check your own.

How long it takes, and living through it

Twelve months is a realistic minimum for anything beyond a simple drain repair, and twelve to twenty-four months is common where underpinning follows monitoring. The slowness is not obstruction; it is the physics of clay, which needs a full seasonal cycle to reveal whether movement is seasonal or progressive, and repairs done too early simply crack again. Mass concrete underpinning is disruptive enough that you may need to move out for the duration; whether the policy pays for that varies. Two practical points: agree the scope and standard of the repairs, room by room, before estimates are obtained, because expectations diverge more over redecoration than over structure; and photograph everything, from the first crack to the finished plaster.

Selling with an open claim is possible but awkward. The claim must be disclosed, the buyer's lender will want to know the outcome, and the sale usually involves transferring the claim to the purchaser with the insurer's cooperation, often at a reduced price. Where the claim has been accepted and the remedy agreed it is manageable; mid-investigation it is hard. Most owners are better served finishing the claim and selling a repaired, documented house. For the money side of each stage, see our subsidence repair cost guide.

Using your own engineer

You are entitled to instruct your own structural engineer at any stage, and there are moments when it is clearly worth it: when the claim is declined and you believe the cracks are movement; when the proposed remedy does not match the cause you can see (a drain repair where the movement is seasonal, or a tree felling where the ground may heave); when partial underpinning is proposed and you want to understand the junction with the rest of the house; or when monitoring is being cut short. The insurer will usually not pay for that report unless it is agreed in advance, but a subsidence assessment with a full written report, including a crack record and a level survey, costs £495 to £895 + VAT with us depending on the size of the property and the type of movement, correct as of September 2026, and it is the document that turns a disagreement into a discussion between engineers.

If the damage comes back

Cracks reappearing after a repair raise the question of whether it is the old claim or a new one. The usual test is whether there has been a new event. Damage in the same part of the house from the same cause within about two years, some insurers say five, is normally treated as the original claim continuing; the Financial Ombudsman's view is that repairs should be effective and lasting, and it has referred to ten years. A fresh dry summer is generally a new event and a new excess, in the same way a second storm is a second claim. Where the recurrence is down to a defective repair, the remedy lies against the designer or contractor, subject to the usual six-year limitation, which is one more reason to hold the guarantee and the certificate.

Insurance and mortgages after subsidence

Staying with the same insurer is normally straightforward: cover continues after repairs, sometimes with a higher subsidence excess, because an annual policy places no duty on the insurer to keep the old terms. Moving insurer is where people worry. A new insurer has no obligation to take on a house with a history, but most subscribe to the ABI agreement that handles subsidence claims notified within the first year after a change of insurer, and there are specialist insurers who will quote once they understand the cause and the remedy. A property that has been properly investigated, stabilised, repaired and certified should stay both insurable and mortgageable; lenders apply a simple test, continued stability, and plenty of distorted period houses pass it every day.

What makes the difference is the paper trail. Keep the initial appraisal, the monitoring results, the investigation report, the repair specification, the Building Regulations completion certificate where the foundations were touched, the contractor's guarantee (ten years is now the norm, and insurance-backed is better than a bare company promise) and the engineer's Certificate of Structural Adequacy, which records the cause, the works, the approvals and the inspections. That bundle answers the questions a buyer's solicitor, surveyor and lender will ask in that order. Occasionally an insurer settles by a once-and-for-all payment for loss of value rather than repair; if that happens, future subsidence cover is normally excluded, so take advice before accepting.

If you disagree with the insurer

Disputes cluster around four things: whether the damage is subsidence at all, whether a condition was breached, the scope of the repairs, and which of two insurers is responsible for movement that straddled a change of policy. Get the reasons in writing, put your own engineer's evidence against them, and use the insurer's complaints procedure. If that does not resolve it, the Financial Ombudsman Service can consider the complaint at no cost to you, but only after the insurer's own process has been exhausted. The FCA's rules require claims to be handled promptly and fairly and not rejected unreasonably, and those words carry weight in a complaint.

New homes: the warranty route

If the house is under ten years old, the first call is the structural warranty provider (NHBC, LABC Warranty and similar), not the buildings insurer. A warranty claim does not need a peril to be proved, only a defect: in the first two years the builder puts it right, and after that the warranty does. Report cracks of more than a millimetre promptly, because failing to report structural movement within the ten years can lose the cover. The warranty runs with the house, so it transfers on sale without paperwork.

Where EMA Structures fits

We act for owners as the independent engineer on subsidence claims: inspection, a written opinion on cause and remedy, and where needed the crack and level monitoring, trial pits and drain surveys that make the argument. Because we also design, and through our specialist construction arm can deliver, crack repairs, structural repairs and underpinning under engineering oversight, our advice on what a repair should involve is grounded in how it will actually be built, and we issue the Certificate of Structural Adequacy at the end of work we have designed and inspected. Start with a subsidence assessment, or send us photographs of the cracks for an honest first view.

This article describes general practice under typical UK household buildings policies as at September 2026. It is not insurance or legal advice; policy wordings, excesses and limits differ, and you should read your own policy and, where a claim is contested, take advice from a broker or a solicitor.