Emergency Plumbing Tips

Plumbing emergencies do not happen at convenient moments. They happen at midnight on a Sunday, or on Christmas Eve, or when you have just left for a two-week holiday. The difference between a minor inconvenience and serious structural damage — thousands of pounds’ worth — often comes down to what you do in the first ten minutes before an engineer arrives.

This guide covers the most common plumbing emergencies, what to do when they happen, and how to be prepared before any of them occur.

Start Here: Know Your Stopcock

Before any emergency strikes, you need to know where your main stopcock is and that it actually works.

The stopcock is the valve that controls the cold water supply into your home. Turning it off stops water flowing through your internal pipework — which in most emergencies is the single most important action you can take. In most properties it is located:

Under the kitchen sink
In a utility room or cupboard near the front of the property
In a hallway cupboard
Occasionally in a garage or cellar

Turn the stopcock clockwise to close it. If it has not been touched in years, it may be stiff or partially seized. Test it annually — turn it off, check the water stops running, then turn it back on fully. A seized stopcock in a real emergency is a serious problem.

Some properties also have an external stopcock in a chamber beneath a small cover in the pavement or front garden, operated with a specific stopcock key. If your internal stopcock is missing or inaccessible, get a key and locate the external one now, not when water is pouring through your ceiling.

Burst Pipe

A burst pipe is one of the most damaging domestic emergencies. Act quickly and methodically.

Step 1: Turn off the water. Go straight to the stopcock and turn it off.

Step 2: Turn off electricity in affected areas. If water is coming through the ceiling or near sockets, switch off the consumer unit (fuse board) for those circuits. Water and electricity are a dangerous combination. When in doubt, isolate the whole board.

Step 3: Drain the system. Turn on all cold taps to drain the remaining water from the pipes. This reduces the pressure of water still coming through any burst section.

Step 4: Collect the water. Use buckets, towels, and whatever containers you have to limit floor damage. If water is coming through the ceiling, the plasterboard will absorb a lot — place a bucket in the centre and be aware the wet ceiling may bulge before it gives way. You can relieve pressure by carefully piercing the bulge at its lowest point to direct water into a container.

Step 5: Document everything. Take photos and video before you clean up. Your insurer will need evidence.

Step 6: Call a plumber. A burst pipe requires professional repair. Temporary fixes with waterproof tape or pipe repair clamps can buy time but are not permanent solutions.

Major Internal Leak

For a significant but non-catastrophic leak — under a sink, from a joint, from an appliance:

Identify the source before anything else
If there is an isolation valve on the supply pipe to that fixture (a small screw slot on the pipe itself), use a flathead screwdriver to turn it 90 degrees — this isolates just that fitting without shutting off the whole house
If no isolation valve, turn off the main stopcock
Move valuables and furniture away from the wet area
Take photos for insurance purposes
Call a plumber — but this is unlikely to be a 3am emergency if you have contained it

Blocked Toilet

A blocked toilet is unpleasant but rarely an emergency in structural terms — unless it is overflowing.

If the toilet is overflowing: Turn off the water supply to the cistern (there is usually an isolation valve on the pipe behind or beneath it) and do not flush again.

For a partial blockage: A toilet plunger — a cup plunger, not the flat type used for sinks — will clear most blockages. Use firm, rhythmic pressure with the plunger submerged. Give it several attempts before giving up.

Do not use chemical drain cleaners on toilet blockages. They are largely ineffective for solid blockages, can damage older pipework and seals, and create a hazardous situation for any engineer who then has to put their hands near the drain.

Call a professional if: the blockage will not clear with a plunger, you can hear gurgling from other drains when you flush (this suggests a problem further down the system), or the toilet has been slow to empty for some time.

Blocked External Drain

Signs of a blocked external drain include water pooling around an outside drain cover, multiple internal drains backing up simultaneously, or unpleasant smells from drainage covers.

You can lift most drain covers with a screwdriver. If the chamber beneath is full, the blockage is downstream. You can attempt to clear it with drain rods (available to hire), but if the blockage is significant, in a sewer rather than your private drain, or recurring, you need a drainage specialist rather than a general plumber.

No Hot Water

Before calling an engineer, work through these checks:

Check the boiler pressure. Most combi and system boilers need 1–1.5 bar to function. If it has dropped, repressurise it (see your boiler manual).
Check the thermostat. Has it been turned down accidentally? Is it set to the correct time programme?
Check the zone valve or hot water cylinder thermostat if you have a separate hot water cylinder.
Try resetting the boiler once. Hold the reset button for a few seconds. If it fires, observe it — if it locks out again quickly, stop. Repeated resets can mask a fault and cause damage.

If none of these resolve it, you need an engineer. This is usually not a same-day emergency unless you have young children or vulnerable people in the household, though some engineers will attend urgently.

Frozen Pipes

Pipes in loft spaces, external walls, and unheated outbuildings are vulnerable in hard frosts. A frozen pipe may not burst immediately but can do so when it thaws if the ice has expanded enough to crack the pipe.

To thaw safely:

Apply gentle heat using a hairdryer on a low setting, starting from the tap end and working back
Warm towels soaked in hot water wrapped around the pipe also work
Never use a blowtorch or naked flame — this can melt plastic fittings, damage the pipe, and create a fire risk

Have a towel and bucket ready in case the pipe has cracked and begins to leak as it thaws. If it does, turn off the water immediately.

To prevent freezing:

Lag exposed pipes in lofts and outbuildings with foam lagging (available cheaply from any hardware shop)
Keep the heating on a low setting (around 10–12°C) when away in winter rather than off completely
Know where your stopcock is so you can isolate quickly if a pipe does burst

Gas Leak

A gas leak is the only plumbing emergency where the right response is to get out of the building — not to try to fix anything yourself.

If you smell gas:

Do not turn any electrical switches on or off
Do not use your mobile phone inside the property
Do not light any flames or use any ignition source
Open doors and windows if you can do so quickly
Turn off the gas supply at the meter if it is safe and accessible (turn the handle 90 degrees so it is across the pipe)
Leave the building immediately
Call the National Gas Emergency number from outside: 0800 111 999 — this is free and available 24 hours a day

Do not return inside until the emergency services have confirmed it is safe.

Building a Home Emergency Kit

A small kit stored somewhere accessible means you spend less time searching for things when something is going wrong. It should contain:

A stopcock key (if you have an external stopcock)
A radiator bleed key
Waterproof pipe repair tape (a temporary fix while you wait for the engineer)
A torch with working batteries
Buckets (at least two)
Old towels
The name and number of your preferred local plumber
National Gas Emergency number: 0800 111 999
Your home insurance emergency claim number

Finding an Emergency Plumber

Emergency callout rates are considerably higher than standard rates. Expect to pay a premium for evenings, weekends, and bank holidays — often £100 or more just for the callout, before any labour or parts. This is standard across the industry.

Before agreeing to any emergency work, ask:

What is the callout charge?
How is labour charged — by the hour or by the job?
Can they give you any indication of cost before starting?

For non-critical issues (such as a contained leak or no hot water), consider whether it can wait until normal working hours when rates are lower. If you need someone immediately, use PlumbingPark to find local emergency plumbers in your area who are available out of hours.

Always confirm Gas Safe registration over the phone before agreeing to any engineer attending for gas or heating work, even in an emergency.