Is my upstairs neighbour automatically liable for the damage?

No. Liability in negligence or nuisance requires fault, and a pipe that fails without warning is not automatically anyone’s fault. The damage to the fabric is usually handled through the block’s buildings insurance instead, with the lease deciding who carries the excess.

Who claims on the buildings insurance, me or the freeholder?

The freeholder arranges the block policy, so the claim normally goes through them or their managing agent. LEASE’s guidance is that you need to ask your landlord to make the claim. Your own contents insurer handles your belongings separately.

My neighbour will not let anyone in. What now?

Ask the freeholder or managing agent to use the access power the lease almost always gives them to investigate a problem, and put the request in writing. LEASE notes the lease may require you to cover their costs of doing so.

The flat above says the leak is not theirs. How is that settled?

By testing rather than by argument. Isolating and pressure testing each flat’s services shows which circuit is losing water, and thermal imaging and moisture mapping show the direction the wetting travelled. A survey that clears the flat above is as useful as one that does not.

Can I withhold service charge until it is fixed?

Withholding service charge is a serious step with its own consequences and is not a remedy for a leak. LEASE directs leaseholders to the repairs process and, ultimately, to legal advice. Take advice before stopping payments.

Leak From the Flat Above: Who Pays

Your upstairs neighbour is not automatically liable simply because the water came from their flat: who pays depends on what caused the leak, what the lease says about that part of the building, and whether the block’s buildings insurance responds — which is why establishing the cause comes before the argument about money.

Leak Fix LondonLast updated 19 September 2026

The assumption that costs people months

The usual assumption is that water from the flat above means the flat above pays. In English law it generally does not work that way. Liability in negligence or nuisance needs fault, and a pipe that fails without warning inside a wall is not obviously anybody's fault. Meanwhile the damage to the fabric of your flat is normally a buildings insurance matter, and the buildings insurance for a block of flats is arranged by the freeholder, not by either of you.

So the sequence that actually resolves it is: find the cause, work out who is responsible for that part under the lease, then see whether insurance responds and who carries the excess. Arguing about money before the cause is established is how these run for six months.

Step one: stop it and record it

Knock on the door. The Leasehold Advisory Service's guidance on water leaks in leasehold flats puts this first: speak to the owner or tenant, and also tell your landlord (freeholder) or managing agent. If nobody answers and water is still coming through, the block may have a communal stop valve, and in a genuine emergency involving electrics or structural risk, the fire brigade is a legitimate call.

Then document it. LEASE advises getting proof of the cause once the leak is found, "such as photographs, or a report from a builder or plumber", because "you may need this for an insurance claim or if there's a disagreement". What to record before anyone attends is the practical version of that.

Step two: what actually caused it

This is the fork in the road, and in London conversions it is very often not what everyone assumed.

Cause	Who is usually responsible
Their appliance: washing machine hose, dishwasher, overflowing bath	The upstairs occupier. Closest to genuine negligence, especially a bath left running
A pipe serving only their flat	Them, under the lease, even where part of the pipe runs outside their flat
Failed shower tray, seal or tanking in their bathroom	Them, usually, though a long-standing failure raises its own insurance questions
A communal riser, cold water tank or boiler serving more than one flat	The freeholder
Roof, parapet, external wall or a defect in the structure	The freeholder
Not their flat at all: your own concealed pipework, a soil stack, condensation	Whoever the demise makes responsible, which may be you

LEASE puts the general division plainly: each leaseholder is usually responsible for "pipes serving their own flat, even if part of the pipe is outside the flat" and for their own appliances, while the landlord is usually responsible for "communal pipes, water tanks or boilers that serve more than one flat" and for leaks caused by a problem with the structure. It then adds the sentence everything turns on: "check the terms of your lease carefully, because leases can vary."

Water travels. A leak on a cold feed in a hallway can appear three metres away above your kitchen, and a ceiling wet at one end of a room regularly has its source at the other. That is the case for finding it properly rather than guessing from the stain, and for the flat above it is worth understanding that a survey which clears their pipework is as valuable to them as one that finds it.

Step three: the insurance, and the excess

Damage to the fabric of your flat — ceilings, plaster, fitted kitchen units, decoration — is normally a claim on the block's buildings policy, which your freeholder arranges and which you contribute to through the service charge. LEASE notes that buildings insurance should cover repairs and redecoration to the fabric, that your landlord is responsible for arranging it and that you will need to ask them to claim. Your furniture, electricals and belongings are contents, and sit on your own policy or possibly on your neighbour's if theirs covers third party damage.

Two things complicate it:

Negligence can defeat the claim. LEASE is explicit that the insurer "might not pay if the damage was caused by negligence, such as leaving a bath running or taking too long to fix a problem". Delay is the one people forget. A neighbour who knew and did nothing for a month has created a problem for both of you.
The excess has to land somewhere. LEASE: the excess "might be recoverable from the person who was responsible for the leak, or it might be shared by all leaseholders through the service charge. This will depend on what the lease says." On a block that has had repeated escape of water claims, that excess can be substantial, and LEASE warns the policy may no longer cover leaks at all, in which case the landlord "might expect you to cover the cost of any repairs yourself or by negotiating with your neighbour".

When the flat above will not cooperate

This is the genuinely difficult part, and the answer is almost never to escalate directly with the neighbour.

Go to the managing agent or freeholder, in writing. LEASE: if your neighbour is not cooperating, ask the landlord or managing agent to help, and they "will usually have a power under the lease to get access to a flat to investigate a problem, although the lease may say that you need to cover their costs". They can also "legally require your neighbour to do repairs", and they hold the owner's and any tenant's contact details.
Put the request in terms of investigation, not blame. A neighbour who thinks they are being asked to admit fault says no. A neighbour asked to allow a non-invasive survey that may clear their flat entirely usually says yes.
Keep every message. Dates of contact and refusals matter later, both to the agent and to the insurer.
If the flat above is rented, the person you need is the landlord, not the tenant. See landlord water leak responsibility.
Legal action is available and is a last resort. LEASE's own position is that where insurance does not cover the damage and a neighbour refuses to pay, it is possible to take legal action "but this should be a last resort", with advice from a solicitor.

In the meantime, protect your own position: keep the damage documented, keep drying it, and do not strip out the evidence.

What we can and cannot do

We can attend either flat, isolate and pressure test the services, survey with thermal imaging and moisture mapping, and where needed use tracer gas on a drained circuit, and then say in writing where the water is coming from and what has to be opened to reach it. That finding is frequently what unlocks a stalled claim, because it replaces two opinions with one measurement.

We do not decide liability, allocate the excess or interpret your lease. Detection is charged at our hourly rate, agreed before we attend, with no fee for the time spent looking if we do not find it. Trace, access and reinstatement covers the repair and putting the ceiling back afterwards.

Frequently asked

Is my upstairs neighbour automatically liable for the damage?: No. Liability in negligence or nuisance requires fault, and a pipe that fails without warning is not automatically anyone’s fault. The damage to the fabric is usually handled through the block’s buildings insurance instead, with the lease deciding who carries the excess.
Who claims on the buildings insurance, me or the freeholder?: The freeholder arranges the block policy, so the claim normally goes through them or their managing agent. LEASE’s guidance is that you need to ask your landlord to make the claim. Your own contents insurer handles your belongings separately.
My neighbour will not let anyone in. What now?: Ask the freeholder or managing agent to use the access power the lease almost always gives them to investigate a problem, and put the request in writing. LEASE notes the lease may require you to cover their costs of doing so.
The flat above says the leak is not theirs. How is that settled?: By testing rather than by argument. Isolating and pressure testing each flat’s services shows which circuit is losing water, and thermal imaging and moisture mapping show the direction the wetting travelled. A survey that clears the flat above is as useful as one that does not.
Can I withhold service charge until it is fixed?: Withholding service charge is a serious step with its own consequences and is not a remedy for a leak. LEASE directs leaseholders to the repairs process and, ultimately, to legal advice. Take advice before stopping payments.

Sources

No find, no fee · £150 per hour. The rate is fixed before we attend and does not rise for a difficult property, an awkward access or an evening visit. The total depends on how long the job takes; the rate cannot change.