Guides · Harrow

Blocked Drains and Home Insurance: What Is Covered

Drainage claims are among the most commonly misunderstood parts of a buildings policy, and the distinction that matters is simple: insurers generally cover sudden damage, not maintenance. This page sets out what that means in practice, and what to check on your own policy before you assume either way. This is general guidance rather than advice on your specific cover - your policy wording is what governs.

What is usually covered

Most buildings policies cover accidental damage to underground services, which typically includes drains, and damage caused by insured events such as subsidence, heave or impact. Collapse of a drain run, or damage from ground movement, generally falls within that. Many policies also include trace and access cover, which pays the cost of finding and getting to the damage - excavating a driveway to reach a collapsed pipe, for example - and that can be the larger part of the bill. Damage inside the property caused by escaping water from a defective drain is normally covered as well.

What is usually not covered

Blockages caused by ordinary use are excluded on almost every policy. Fat, wipes, foreign objects and general build-up are treated as maintenance, not as damage. Gradual deterioration is also excluded - an old clay pipe that has slowly degraded over decades is wear and tear, however expensive the consequence. Root ingress sits awkwardly between the two: some insurers treat it as gradual damage and decline, others cover it where the resulting damage was sudden. This is one of the more variable areas between policies, so it is worth checking the specific wording.

Why the CCTV survey usually comes first

An insurer will want evidence of what the damage is and what caused it before considering a claim, and that means a survey report and footage. It is worth telling the drainage firm at the outset that this may become an insurance claim, so the survey is documented appropriately from the start - a clearance carried out without a record leaves you with a bill and no evidence. Where the survey shows the problem was a blockage rather than damage, you will have found that out for the cost of a survey rather than the cost of a declined claim.

The order to do things in

Stop the immediate damage first - an insurer will not penalise you for preventing a situation getting worse, and most policies require you to take reasonable steps. Then check whether the pipe is even yours before claiming: if the fault is on a Thames Water lateral drain or public sewer, they deal with it and there is no claim to make. Then get the survey. Then notify your insurer before commissioning any repair work, because work carried out without their agreement is frequently refused. Photograph everything at each stage.

If you are a landlord or a leaseholder

Landlords should check whether their policy covers underground services and trace and access, as some landlord products differ from standard household cover. Leaseholders in converted or purpose-built flats should establish before doing anything who insures the building - usually the freeholder or management company through a block policy - because a leaseholder claiming on their own contents policy for a structural drainage problem is claiming under the wrong cover. Shared drainage in converted properties across the borough is common, and establishing responsibility early avoids paying for a run that is a building-wide liability.

Common questions

Is a blocked drain an emergency for insurance purposes?

Home emergency cover, where you have it, often includes drainage blockages that make a property uninhabitable or unsanitary - but it is usually a separate add-on rather than part of standard buildings cover, and typically caps the amount paid. Check whether you have it before calling a firm out at emergency rates.

Will claiming affect my premium?

It may, and for a modest clearance the claim is often not worth making once the excess is taken into account. Where the work involves excavation, repair and reinstatement, the figures are usually large enough that a claim makes sense. Compare the likely repair cost against your excess before deciding.

What if the damage was caused by a neighbour's tree?

Where roots from a neighbouring property have damaged your drainage, there may be a claim against them or their insurer, though these situations usually turn on whether the pipe was already defective. Your own insurer may pursue it on your behalf. Document the evidence with a survey and take advice before approaching the neighbour.