Subsidence report for insurers
An inspection and report on suspected subsidence, heave or settlement, written so your insurer or loss adjuster can assess the claim.
About this service
A subsidence report for insurers is a structural engineer's inspection and written assessment of suspected subsidence, heave or settlement. It is written with a buildings insurance claim in mind, so it sets out the evidence clearly, categorises the cracking against recognised damage categories and gives a reasoned view on the likely cause. Your insurer or loss adjuster can then assess the claim on solid ground.
Homeowners commission this report when new cracks appear or existing ones widen, especially after a hot, dry summer. Insurers sometimes ask the policyholder to provide one, and owners also use it when they disagree with the insurer's initial findings and want an independent engineering view. Landlords use it to protect the value of a property while a claim is in progress.
Subsidence is a particular risk in London because so much of the city sits on London Clay. This clay shrinks as it dries and swells as it wets, and tree roots can draw moisture from well below shallow Victorian foundations. Leaking drains can also soften or wash out the ground beneath a wall. Telling these causes apart matters because the repair and the claim depend on it.
Each report is signed off by a chartered engineer who is a Member of the Institution of Civil Engineers (MICE). We describe crack patterns, widths and directions, and explain how they fit with the likely mechanism, so the report is useful whether the claim is straightforward or disputed. Reports start from £550 + VAT, with the fixed fee confirmed in writing before we visit.
When you need it
- You've noticed new or growing cracks and suspect subsidence
- Your insurer has asked for a structural engineer's report
- You're disputing an insurer's findings
What's included
- Inspection of the cracking and movement
- Assessment of likely cause, such as trees, drains or soil type
- Crack categorisation to recognised guidance
- Recommendations for investigation, monitoring and repair
How it works
- Tell us what you have seenShare when the cracks appeared, how they have changed, any insurer correspondence and photos. We confirm the scope and fixed fee in writing before visiting the property.
- Inspect the movementAn engineer inspects inside and out, measuring crack widths, mapping patterns, checking levels and noting nearby trees, drains, ground slopes and any extensions with different foundations.
- Categorise the damageCracks are categorised against recognised guidance on damage severity, from hairline cosmetic cracking to severe structural damage, giving the insurer and adjuster a common reference point.
- Assess likely causeWe weigh the evidence for clay shrinkage, heave, drainage leaks, settlement and other causes, and explain our reasoning so the conclusion can be followed and checked.
- Report and recommendationsThe MICE-signed report recommends next steps, such as monitoring, drainage survey, soil testing, tree management or repair, and is ready to pass to your insurer or loss adjuster.
What you receive
Subsidence, heave or settlement: why the cause shapes your claim
Insurers treat these mechanisms differently. Subsidence is downward movement of the ground below foundations, often from clay drying or leaking drains. Heave is the opposite, typically after a large tree is removed and clay swells. Settlement is the normal compression of ground under a new load, often in the first years after building, and is usually excluded from cover. Our guide on subsidence signs explains the warning signs in plain terms.
Common recommendations include a CCTV drainage survey to check for leaks, soil and root sampling, and a period of crack monitoring to show whether movement is seasonal or progressive. Where trees are involved, the solution may be tree management rather than underpinning, and our guide on London Clay and trees covers why.
The biggest pitfall is repairing cracks before the claim is assessed. Filling and redecorating removes the evidence the insurer needs. Photograph everything, note dates, tell your insurer promptly and get an engineer's view before any repair.
Not included
- Arboricultural, drainage or soil testing, which can be arranged separately
Frequently asked questions
How do I know if cracks in my house are subsidence?
Subsidence cracks are often diagonal, wider at the top or bottom, and found near doors and windows. They may appear or widen in summer, and doors and windows may start to stick. Cracks in both the inside and outside face of the same wall are a strong sign. An engineer can confirm by looking at the pattern and surroundings.
Do I need a structural engineer's report for a subsidence claim?
Many insurers appoint their own adjuster and engineer, but some ask the policyholder for a report, and others accept one in support of a claim. An independent report is also useful if you disagree with the insurer's view. Check with your insurer before commissioning, so the report adds to their process rather than duplicating it.
What causes subsidence in London?
The most common cause is shrinkage of London Clay as trees and dry weather draw moisture from the ground, which can affect shallow foundations on older homes. Leaking drains that soften or erode the ground are another frequent cause. Less often, made ground, old excavations or nearby works can be responsible.
Will subsidence make my house hard to sell or insure?
It can make insurance and sale more complicated, but it does not make a property unsaleable. Buyers and lenders mainly want to see that the cause was identified, the movement has stopped and repairs were completed. A clear engineer's report and a certificate of structural adequacy after repairs help considerably.
Does subsidence always need underpinning?
No. Many subsidence cases are resolved by removing the cause, such as repairing a drain or managing a tree, followed by monitoring and crack repairs. Underpinning is generally reserved for cases where the cause cannot be removed or the foundations are clearly inadequate.