Leak from the flat above: what to do first

By Emergency Plumb, 26 October 2026

A brown ring spreading across the ceiling, a drip from the light, the sound of water inside the wall. When you live in a flat and the bathroom above is someone else’s, the hardest part of the leak is that the tap you need to turn is behind a door you cannot open. This guide is about getting it stopped quickly anyway.

Short answer: Go upstairs and knock. If they are in, ask them to turn off their stopcock and stop using the bath, shower and washing machine. If nobody answers, try your own stopcock, then the building’s managing agent or landlord, then us. Below the leak, switch off the lighting circuit at the consumer unit if it is safe, put a bucket under the drip and photograph everything.

The first ten minutes

Knock upstairs, and keep knocking. Most leaks from above are a shower tray, a bath waste, a washing machine hose or a toilet that has started weeping. If your neighbour is home, they can close their own stopcock in seconds. It is usually under the kitchen sink, in a hall cupboard or next to the hot water cylinder.
Close your own stopcock. In a purpose-built block this rarely stops water coming from above, but in a Victorian house that was split into two or three flats, the plumbing is sometimes still shared. If the drip slows within a few minutes of turning yours off, the leak is on a pipe that serves you as well.
Make the electrics safe. Water follows joists and cables to the nearest light fitting. Do not use the wall switch. Turn off the lighting circuit at your consumer unit if you can get to it while dry.
Catch the water. Buckets, a washing-up bowl, towels on the floor. Move rugs, electrics and anything you value out of the room. If the ceiling is sagging, keep everyone out from under it.
Write things down. Note the time it started, take photos and video of the ceiling and any damage, and keep any messages you send. Insurers and managing agents both ask for this.

When nobody answers the door

This is where London flats make leaks harder. A neighbour may be away for half term, the flat may be let and empty between tenants, or it may be a short let with no one there for days.

Start with whoever manages the building. Leasehold blocks have a managing agent or a freeholder, and many have an out-of-hours number on the noticeboard by the entrance or in the paperwork you were given when you moved in. Council and housing association blocks have their own repairs line that answers around the clock. If your own flat is rented, tell your landlord or letting agent too; they may hold a key to the flat above or know the owner.

While you are on the phone, look for a shared stopcock. In converted terraces across Haringey, Islington, Hackney and Lambeth it is often in the communal hallway, under the stairs, in a basement or in a small chamber in the front path. In mansion blocks and newer purpose-built blocks, individual flats are often isolated from valves in a riser cupboard on the landing. Only close a valve you are sure about, and tell your neighbours you have done it.

Never force a door, climb in through a window or ask anyone else to. If water is pouring through and you cannot reach anyone, call or WhatsApp a photo to 07861 933265. Finding which valve in a building controls which flat is part of the job.

Why it keeps happening from the same place

Repeat leaks from above in London usually trace back to one of a few causes. Shower trays that flex on old timber floors, so the seal cracks every time someone stands in them. Bath wastes and overflows that were never sealed properly when a bathroom was refitted. Toilet pan connectors that slowly push off. Washing machines plumbed in with old hoses. In older conversions, pipework run under floorboards decades ago, with joints that weep once the heating comes on and the timber moves.

The stain on your ceiling is often not directly under the fault. Water can run along a joist for a metre or more before it drips, which is why tracing it properly matters before anyone starts cutting.

What we do when we get there

We start in your flat: confirm the water is coming from above and not from your own pipes, a tank or the roof, and make your ceiling and electrics safe. With access to the flat above, we find the source, using the equipment from our leak detection service where it is needed, then repair it there and then if the part is on the van. Without access, we isolate what we can from the common parts and tell you and the managing agent exactly where the water is coming from.

You pay for the time we are on site: £110 for the first hour, £45 for every half hour after, plus parts, with no call-out charge and no extra for nights or weekends. Work is covered by our 12-month workmanship guarantee.

Afterwards

Let the ceiling dry fully before anyone paints or patches it. A ceiling that was soaked will usually show a stain again if it is decorated too soon. If damp patches keep coming back long after the repair, our guide to finding a hidden water leak explains the signs to watch for.

It is also worth knowing where your own stopcock is before the next one, and whether it still turns. If yours is stiff, see what to do with a seized stopcock.

For water through the ceiling from any source, not just a neighbour, our ceiling leak page covers what we do across London and the M25 towns.

Questions people ask

My neighbour upstairs is not answering. What can I do?

Ring the managing agent, freeholder, landlord or housing association on their out-of-hours line, as they may hold a key or know who does. Look for a shared stopcock in the hallway, the basement or the front garden, which in many converted houses controls more than one flat. Never force your way into somebody else's home. If water is pouring and nobody can be reached, call us; we can often find and close a valve that isolates the flat above from the common parts.

Will turning off my own stopcock stop a leak from upstairs?

Usually not. In most blocks and conversions each flat has its own supply, so closing yours only proves the water is not from your plumbing. In some older houses split into flats, one supply still feeds both, and then your stopcock may slow it. Try it anyway, because it tells you which situation you are in.

Who pays for the damage to my ceiling?

It depends on your lease, the cause and the insurance, so there is no single answer. Report it to your contents insurer and to the managing agent or freeholder straight away, as the building insurance often covers ceilings and structure in a block. Keep photos, dates and the name of whoever you spoke to. The person whose pipe or appliance failed is normally expected to stop the leak and have it fixed.

Is it safe to use the lights under a leak?

No. Leave the switch alone and turn that lighting circuit off at your consumer unit, but only if you can reach it without standing in water or touching anything wet. If the leak is over the consumer unit itself, keep away from it and tell us when you call.

What does it cost to have you come out?

There is no call-out charge. The first hour is £110, each half hour after that is £45, and parts are extra. It is the same rate at midnight on a Sunday.