Expertise / Subsidence
Subsidence engineers
Finding the true cause of movement, assessing the damage, and setting out the repair. Reports that insurers, loss adjusters and homeowners can act on.
We regularly investigate subsidence-related claims, identifying the true cause of movement, assessing damage and recommending appropriate remediation. Our investigations may include trial holes, drainage surveys, monitoring and specialist testing.
AOCA carries out several hundred insurance-related inspections every year across Ireland and the UK. Subsidence is among the most common, and the most often misdiagnosed. Cracking that looks alarming is frequently seasonal movement or a leaking drain; cracking that looks minor can be the first sign of foundation failure. The investigation tells the difference.
What causes subsidence
Most Irish subsidence comes from one of four things: shrinkable clay soils drying out, often made worse by nearby trees; leaking or collapsed drains washing fines from beneath the foundation; poorly compacted fill under an extension or a later addition; and, less commonly, mining, peat or made ground settling over time.
Heave, the opposite movement, happens when a clay soil takes on water after a tree is removed. It produces similar cracking and needs the same discipline of investigation.
How we investigate
An inspection starts with the crack pattern, the age and construction of the building, and the ground and drainage around it. Where the cause is not clear from the inspection we use trial holes to see the foundation and the soil beneath it, drainage surveys with a camera, level and crack monitoring over a period of months, and laboratory testing of soil samples where clay shrinkage is suspected.
The report sets out the cause, the extent of damage, whether movement is progressive or historic, and what has to happen next. Where a policy is involved it addresses the policy definitions directly.
Remediation
Not every subsidence case needs underpinning. Repairing a drain, managing a tree or allowing a season of monitoring is often the right answer. Where structural repair is needed we design it: underpinning, piled solutions, grout stabilisation or resin injection, and the crack repair and redecoration that follow. We can act as engineer through the works and certify them on completion.
Expert witness
We regularly provide expert witness services, drawing on years of direct project experience. From subsidence and structural failures to insurance claims and dispute resolution, our engineers offer clear, objective and practical technical evidence that reflects real-world engineering challenges and solutions.
Common questions
Is every crack subsidence?
No. Most cracks in Irish homes are from thermal and moisture movement, lintel deflection or settlement of a newer extension, and are not progressive. Diagonal stepped cracking wider than about 5 mm, cracks that widen over months, doors and windows sticking, and cracking near drains or trees are the signs worth an inspection.
Who instructs AOCA on a subsidence claim?
Insurers, loss adjusters and loss assessors instruct us directly. Homeowners and solicitors also instruct us for independent reports, second opinions and expert witness work.
How long does an investigation take?
The first inspection and report are quick. Where monitoring is needed to prove whether movement is ongoing, the monitoring itself runs over a period of months, and we say at the outset how long and why.
Do you cover all of Ireland?
Yes, from the Portlaoise and Dublin offices, and the UK from Manchester.
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