Not every plumbing problem needs panic. Some small issues can be understood, contained or even fixed with a simple replacement part. Others need a qualified plumber straight away. The tricky bit is knowing which is which.
Before you call a plumber, it is worth doing a few simple checks. These can help you explain the problem clearly, reduce the risk of further damage, and avoid paying for a callout when all you need is a washer, hose, trap, connector or bit of practical advice.
This guide is for everyday household plumbing issues, such as dripping taps, small leaks, slow-draining sinks, loose fittings, leaking waste traps and minor problems under the sink. It is not a guide for major plumbing work, gas appliances, boilers, hidden leaks, sewage problems or anything that feels unsafe.
If there is a serious leak, water near electrics, a collapsed ceiling, sewage backing up, no water supply, or a smell of gas, do not wait. Turn off the water if it is safe to do so and call the right professional or emergency service.
First, is it an emergency?
Before doing anything else, decide whether the problem needs urgent help.
Call a plumber straight away if water is coming through a ceiling, a pipe has burst, a leak is spreading quickly, you cannot turn the water off, or the problem is affecting electrics. You should also call a professional if you cannot see where the water is coming from, if the leak is inside a wall or floor, or if the same problem keeps coming back.
If you smell gas, do not treat it as a plumbing repair. Open doors and windows if safe, avoid using electrical switches, do not smoke or use naked flames, and call the National Gas Emergency Service on 0800 111 999.
For smaller problems, such as a drip under the sink, a tap that will not stop dripping, a loose waste pipe, or a slow drain, you may have time to check a few things first.
1. Find out where the problem is coming from
Start by identifying the source of the issue as clearly as you can.
With a leak, wipe the area dry first, then watch carefully to see where the water appears. Water can travel along pipes, cupboard bases, tiles and worktops, so the wettest place is not always the source of the leak.
Common places to check include:
Under the sink, especially around the waste trap, pipe joints, flexible tap connectors and washing machine or dishwasher hoses.
Around taps, especially where the tap meets the basin, sink or bath.
Behind toilets, particularly around the inlet pipe, isolation valve, cistern and waste connection.
Around radiators, especially valve connections and visible pipework.
Around appliance hoses, especially where washing machines and dishwashers connect to the water supply and waste pipe.
If the problem is a blockage rather than a leak, check whether it affects one drain or several. A slow bathroom basin may simply be blocked with hair and soap residue. A kitchen sink may be affected by grease or food debris. If several drains are backing up at once, the problem may be more serious and you should call a professional.
2. Turn off the water if needed
If water is actively leaking, turn it off before investigating further.
For a small local leak, such as a dripping tap connector or leaking toilet inlet, look for an isolation valve close to the fixture. These are often small valves fitted to the pipe, usually turned with a flathead screwdriver. When the slot is in line with the pipe, it is usually open. When the slot is turned across the pipe, it is usually closed.
For a larger leak, or if you cannot isolate the individual fixture, use your main stop tap. This is commonly found under the kitchen sink, in a utility room, downstairs toilet, airing cupboard, hallway cupboard, cellar or near where the water pipe enters the property.
It is a good idea to know where your stop tap is before you need it. If it is stiff, stuck or difficult to reach, ask a plumber to check it. In an emergency, being able to turn the water off quickly can make a big difference.
3. Take clear photos before moving anything
Before unscrewing, tightening or removing anything, take a few photos.
Take one wider photo showing where the problem is, then a few close-up photos of the fitting, pipe, washer, hose, valve, trap or connector. If there is a visible part number, size mark or thread, photograph that too.
This is especially useful if you plan to visit Collins Hardware for advice. A photo helps the team understand what you are looking at, even if you are not sure what the part is called.
For example, instead of trying to explain “the plastic bit under the sink”, a photo can show whether you are dealing with a bottle trap, P-trap, compression fitting, waste washer, overflow connection or appliance hose connection.
4. Check whether anything is loose, split or misaligned
Some minor leaks are caused by simple movement.
Under sinks and basins, waste pipes can become slightly loose if items are pushed against them in the cupboard. Washing machine hoses can be knocked. Sink traps can move when cleaning products, bins or storage baskets are placed around them.
Look for obvious signs:
A loose plastic nut on a waste trap.
A pipe that no longer lines up neatly.
A rubber washer that has perished, cracked or slipped out of position.
A hose that is kinked, stretched or rubbing.
A joint that is wet only when the tap is running.
A leak that appears only when the washing machine or dishwasher drains.
Be careful with tightening. Plastic fittings can crack if overtightened, and compression fittings can be damaged if forced. If something feels stuck, brittle, badly aligned or under strain, it is better to stop and get advice.
5. Work out when the problem happens
A useful question is: does the problem happen all the time, or only when something is used?
If water appears only when you run the tap, the issue may be with the waste pipe, trap or sink overflow.
If water appears even when the tap is not being used, the issue may be with the supply pipe, tap connector, valve or pipework.
If a toilet keeps refilling, hissing or running into the pan, the problem may be inside the cistern.
If the floor is wet after using the washing machine or dishwasher, check the appliance hoses, waste connection and surrounding pipework.
If the sink drains slowly after washing up, the issue may be a partial blockage in the trap or waste pipe.
This information is useful whether you are trying a small fix yourself, asking for advice in store, or calling a plumber. It helps narrow down the likely cause.
6. Check the simple things first
Some plumbing problems look worse than they are.
A slow-draining sink may be caused by debris in the trap. A leaking shower hose may need a new washer. A dripping outside tap may need a replacement hose washer or tap washer. A leak under the sink may be a waste fitting that has worked slightly loose.
Before assuming the worst, check:
Is the tap fully turned off?
Is the plughole blocked with hair, food or debris?
Is the sink trap full of residue?
Is a hose washer missing or damaged?
Is a connector cross-threaded?
Has something in the cupboard knocked the pipework?
Is the leak clean water, dirty water, or condensation?
Condensation is worth mentioning because it can be mistaken for a leak. Cold pipes, toilet cisterns and some areas under sinks can collect moisture, especially in colder months or poorly ventilated spaces. If the area is only lightly damp and there is no clear drip, wipe it dry and check again later.
7. Do not ignore repeat problems
A one-off blocked sink may be easy to deal with. A sink that blocks again and again is different.
Repeat problems usually mean there is an underlying cause. It could be pipe layout, a deeper blockage, poor fall on the waste pipe, damaged fittings, old pipework, hard water build-up, or something further along the system.
The same applies to leaks. If you keep tightening the same fitting, replacing the same washer, or putting a bucket under the same pipe, it is time to get the issue properly checked.
Small leaks can damage cupboards, floors, plaster, tiles and ceilings over time. The sooner the cause is found, the less damage it is likely to do.
8. Make a note of the part you may need
If the problem looks like a small repair, try to identify the part before heading out to buy a replacement.
Useful things to bring into Collins Hardware include the old washer, hose, connector, trap section, tap insert, valve, screw fitting or any packaging from the previous part. If you cannot remove the part safely, bring photos and measurements instead.
Helpful measurements include:
The diameter of the pipe.
The length of the hose.
The size of the washer.
The type of thread or connector.
The distance between fittings.
The make or style of the tap, if known.
Do not worry if you do not know the correct name. Most people do not. A clear photo, the old part, or a rough description of where it came from is usually a good start.
9. Know which jobs are not DIY jobs
Some jobs are best left to a professional.
You should call a plumber for hidden leaks, burst pipes, major pipework changes, low water pressure affecting the whole property, repeated blockages, leaks near electrics, water coming through ceilings, problems with hot water cylinders, and anything where you cannot safely isolate the water.
You should also avoid DIY work on boilers, gas appliances or gas pipework. Those jobs need a Gas Safe registered engineer.
The aim of checking first is not to avoid using a plumber when one is needed. It is to understand the problem, reduce damage, and make sure you are asking for the right help.
10. What to tell the plumber if you do call
If you decide to call a plumber, have the key details ready.
Tell them:
Where the problem is.
When it started.
Whether the water is still running or has been turned off.
Whether the leak is clean water, waste water or unknown.
Whether it happens all the time or only when something is used.
Whether you can see the source.
Whether the area is near electrics.
Whether you have photos.
Whether you have tried anything already.
This helps the plumber judge how urgent the job is and whether they may need specific parts or equipment.
Quick checklist before calling a plumber
Before calling a plumber, check whether the issue is urgent, turn off the water if needed, find the source of the leak or blockage, take clear photos, check whether any fittings are loose or damaged, note when the problem happens, and gather details of any parts that may need replacing.
If the problem is small and visible, Collins Hardware may be able to help you identify the part you need. Bring in the old part if it is safe to remove, or take a few photos and measurements.
If the problem is serious, hidden, spreading, near electrics, connected to gas, or keeps coming back, call a qualified professional.
FAQs
Should I call a plumber for a small leak?
You should call a plumber if the leak is spreading, hidden, near electrics, coming through a ceiling, or cannot be isolated. For a small visible leak under a sink or around a hose connection, you may be able to check the fitting, washer or trap first. If you are unsure, get advice before taking anything apart.
What should I do first if a pipe is leaking?
If it is safe, turn off the water supply. Use a local isolation valve if the leak is limited to one fixture, or use the main stop tap for a larger leak. Move items away from the water, place a bucket or towel under the leak, and call a plumber if the leak is serious or you cannot stop the flow.
What should I bring to a hardware shop for plumbing advice?
Bring the old part if it is safe to remove. If not, bring clear photos and measurements. Useful details include pipe size, hose length, washer size, fitting type, where the part came from and what happens when the problem occurs.
Can I fix a dripping tap myself?
Some dripping taps can be fixed by replacing a washer, O-ring or cartridge, but it depends on the type of tap. Turn off the water before taking anything apart. If the tap is old, seized, damaged or difficult to identify, take photos or bring the old part into Collins Hardware for advice.
When should I not try a plumbing repair myself?
Do not attempt a repair if the leak is hidden, water is near electrics, the ceiling or floor is affected, the problem involves gas, the water cannot be isolated, or you are unsure what you are working on. In those cases, call a qualified professional.