The clause, and why it exists
Almost every home wording carries some version of an exclusion for loss or damage arising from gradually operating causes: deterioration, wear and tear, corrosion, rot. The Financial Ombudsman Service refers to it as a "gradually operating clause" exclusion.
The logic is not unreasonable. Insurance is for events, not for the slow decay of a building. As the ombudsman puts it on wear and tear, "everything wears out eventually and insurance can't protect you from that".
The difficulty is that almost every concealed water leak is, by its physical nature, gradual. A pinhole in a buried 15mm pipe does not flood a room on a Tuesday. It weeps for months into screed, which absorbs it, while the heating dries it, until a ceiling below finally stains. That is why the exclusion is the most common ground for refusing exactly the claims that trace and access cover was sold to support.
The three-part test that actually decides it
This is the part nobody in the trade tells people, and it is the most useful thing on this page. The ombudsman sets out when it may require an insurer to pay even where damage did happen gradually. All three limbs have to be there:
- "the damage was caused by an insured event covered under the policy, such as, escape of water or flood", and
- "we think you couldn't reasonably have been aware of the damage happening gradually, for example, the damage is concealed behind a kitchen unit or bath panel", and
- "you made the claim, or took reasonable action, as soon as you could reasonably have known about the problem".
Read limb two again. Concealment is the point. A leak inside a wall, under a screed floor, behind a bath panel or inside a floor void is precisely the case the ombudsman describes as one you could not reasonably have been aware of. The physical facts that make an insurer reach for the exclusion are frequently the same facts that defeat it.
Who has to prove what
The burden sits with the insurer, and the ombudsman says so in terms: "If we're not satisfied the insurer has shown the damage happened gradually, we're likely to tell it to accept your claim."
It also says that where an insurer has relied on an exclusion to refuse or reduce payment, it looks at whether the exclusion has been applied fairly. That sits on top of FCA rule ICOBS 8.1.1R, which requires an insurer not to "unreasonably reject a claim".
The practical consequence: do not accept "it looks like it has been going on a while" as a decision. Ask what evidence supports it. An adjuster's impression is not a finding.
What the evidence looks like on each side
The ombudsman says it considers "professional reports and photos about the damage, and whether it happened gradually". Here is what that means on a real job.
| Points towards gradual and excluded | Points towards recent and covered |
|---|
| Black mould growth, layered tide marks, rot in timber | A clean, fresh stain with no mould |
| Long-standing corrosion, scale build-up around the defect | A single pinhole or a failed joint with bright metal at the fracture |
| Historic repairs or paint over the same patch | No previous decoration over the area |
| Previous complaints or reports about the same stain | First report, made as soon as it appeared |
| Visible, accessible pipework left unattended | Pipework buried in screed, behind tiling, or in a sealed void |
In a published ombudsman case study, a small hole in a shower room waste pipe leaked over time and damaged the living room ceiling below. The insurer declined it as gradual damage. The ombudsman upheld the complaint, because the leak was hidden until visible signs appeared, the customer reported it promptly, and photographs showed a fresh stain with no mould or extensive discolouration.
What to do while it is still fixable
- Photograph the stain the day you see it, dated. The single most valuable piece of evidence in a gradual damage dispute is a photograph proving the mark was fresh when you found it.
- Report it immediately. Limb three of the test is about your reaction time, and that is the only limb entirely within your control.
- Do not speculate. Saying "it has probably been leaking for ages" in the first phone call hands the insurer limb two. Describe when you first saw it, not how long you imagine it ran.
- Get the defect identified and photographed. The nature of the failure matters. A split from a freeze, a pinhole from internal corrosion and a joint that was never made up properly are three different stories, and only one of them looks like neglect.
- Record concealment. Photograph the pipe in situ before it is cut out, showing the screed depth, the tiling, the sealed void. That is the physical proof of limb two.
Our leak detection report is built around those five points, and written to be accepted for a trace and access claim. It records the method, the pressure test result that proves an active loss, the located defect, and the state of the surrounding fabric. See trace, access and reinstatement.
Gradual damage is not the same as wear and tear
Worth keeping separate, because the outcomes differ. If an insurer says the damage was caused by wear and tear, the ombudsman is, in its words, "unlikely to tell them to pay the claim". Corroded-through pipework at the end of its life, perished sealant, a roof that has simply aged: those are maintenance. A sudden pinhole in an otherwise sound run that then leaked unseen for weeks is a different argument, and it is the argument the three-part test was written for.
If you are declined
Ask for a final response in writing that quotes the exclusion relied on and states the evidence for it. If it does not arrive within eight weeks, or you disagree with it, refer the complaint to the Financial Ombudsman Service within six months of that response. It is free, and you do not need to pay anyone to represent you. You must have raised the complaint with the insurer within six years of the problem, or within three years of when you could reasonably have realised there was one.
When we would tell you not to bother
If the pipework is genuinely at the end of its life and failing in several places, a claim on a single leak is likely to meet a wear and tear argument you will not win, and the honest advice is to budget for replacing the run rather than fighting about it. We will say so on site rather than after you have spent three months on a complaint.
