The sentence every declined claim contains
Somewhere in the refusal letter there will be a version of this: insurance covers sudden and unforeseen events, it is not a maintenance contract, and your damage happened gradually. It sounds like a rule. It is not. It is a description of a general exclusion, and the interesting question is where the Ombudsman has actually drawn the line when it has had to.
Reading the published decisions, the line is not where most refusal letters put it. Insurers tend to argue duration: the pipe corroded over years, therefore gradual, therefore excluded. The decisions turn on something else.
The Ombudsman’s own three-part test
The Financial Ombudsman Service publishes its approach to gradual damage complaints, and it sets out when an insurer may still have to pay even where damage did occur gradually. Three things have to line up:
- the damage was caused by an insured event covered under the policy, such as escape of water or flood;
- you could not reasonably have been aware of the damage happening gradually, for example because it was concealed behind a kitchen unit or a bath panel; and
- you made the claim, or took reasonable action, as soon as you could reasonably have known about the problem.
Notice what is absent. There is no time limit. Nothing says a leak of more than six months is excluded. The middle limb is doing all the work, and it is a question about knowledge, not about hydraulics.
Gradual cause, sudden loss: the drainage case study
The service publishes a case study under the reference "loss of function sees rejected claim overturned" that shows the distinction cleanly. A homeowner noticed the drainage running slower than normal, tried a sink unblocker, and then called the insurer. A drainage company found a partial blockage in the underground pipework and nothing else wrong.
The insurer refused on two grounds. There was no physical damage to the pipework, because water was still flowing. And the blockage had built up slowly, so the gradual damage exclusion applied.
The Ombudsman upheld the complaint. The blockage met the standard definition of accidental damage as unforeseen and unintentional damage. More usefully, the decision separates the cause from the loss: the material may have accumulated gradually, but the loss of function was not gradual, and the homeowner would only have discovered the problem at the point where the drainage noticeably failed.
That is the distinction to hold on to. A gradual process can produce a sudden loss, and it is the loss the policy responds to.
Long-running and hidden is not the same as excluded
DRN-5970477 makes the same point on a water leak. The evidence in that case was that a shower valve had been leaking behind tiled walls for long enough to heavily corrode the bracket and rot the timber around it. On the insurer’s reading that is textbook gradual damage, and it argued exactly that, pointing to the exclusions for rust, corrosion, wear and tear and lack of maintenance.
The Ombudsman accepted that corrosion would ordinarily be excluded, and still upheld the complaint. The finding was that the service "doesn’t expect the customer to deal with corrosion or wear or tear which isn’t visible or couldn’t have reasonably been known about", and that because the insurer’s own experts had not identified the pipework behind the tiles as the likely cause, the policyholder could not be expected to have done so either.
The leak was old. It was not foreseeable to the person living above it. That was enough.
Where the same argument failed
DRN-5646463 runs the other way, and it is the honest counterweight. A bath stopped draining, the waste pipe below leaked, and before a plumber could attend the kitchen ceiling partially collapsed. That is about as sudden as a domestic loss gets.
Advantage declined under the gradual causes exclusion. Its drainage specialist ran a CCTV survey and found a broken bend, two large displaced joints, and a blockage caused by an old bottle and another object. The specialist’s view was that displacements that size would have taken more than twelve months to develop, and that the drainage system would almost certainly have blocked several times before the claim. The soil stack was badly corroded with age.
The Ombudsman did not uphold the complaint, and the reasoning went through both limbs. On the first, the insurer had shown on the balance of probabilities that the damage occurred gradually. On the second, the decision considered whether the policyholder could reasonably have known, and found that they could: photographs showed mould in the kitchen that was not minor and sat high on the wall close to the ceiling under the bathroom, the exterior of a pipe was visibly heavily corroded, and the drains had probably blocked repeatedly.
The ceiling came down in an afternoon. The claim still failed, because the warning signs had been visible for a long time.
Reading the three together
| Case | How long it had been going on | Outcome |
|---|
| Loss-of-function drainage case study | Blockage built up slowly | Upheld. The loss of function was not gradual. |
| DRN-5970477 | Long-term leak, heavy corrosion | Upheld. Concealed behind tiles and not reasonably knowable. |
| DRN-5646463 | Drainage defects over twelve months | Not upheld. Visible mould and corrosion were signs the policyholder could have acted on. |
Duration does not predict the outcome. Visibility does. The question the decisions keep returning to is when a reasonable person in that house would have realised something was wrong, and what they did about it once they did.
What this changes about how you behave
Two practical things follow, and neither is a legal argument.
The first is that the clock the insurer will eventually care about starts at the first symptom you noticed, not at the point the ceiling fell in. In DRN-5970477 the policyholder’s position was helped considerably by the fact that they had called a plumber to look at a damp wall weeks before any ceiling damage appeared, which showed they had not ignored it. In DRN-5646463 the mould had been treated as condensation from a kettle.
The second is that a symptom you cannot explain is worth dating. A photograph with a timestamp, a note of the meter reading, a text to a plumber. We set out what to capture on documenting a leak before anyone attends. If your boiler is losing pressure and nothing is visibly wet, the boiler pressure pages are the faster route in. And if the meter is turning with everything off, that is a meter question first.
Read this properly
Every decision quoted here was reached on its own policy wording and its own facts. They do not create a precedent, they do not bind your insurer, and none of them tells you what will happen to your claim. If yours has been declined, ask for a written final response naming the clause relied on. The Financial Ombudsman Service reviews complaints free of charge, and you have six months from the date on that final response.
When not to call us
If the answer is obviously condensation, mould in a cold corner with no water source above it, that is ventilation and heating, not a leak. If the damage is rain through a roof, that is not escape of water on any wording we have read, and a detection visit will not change the heading. Where the source genuinely is not visible, we work at £150 per hour agreed before we attend, with no charge for the search if we do not find it. Pricing is on one page.
