How to Sew On a Button and Hem Pants by Hand
The other small repair most people pay someone else for, and shouldn't — same idea, twenty minutes and two tools.
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A blocked sink is the kind of job people either fix in twenty minutes or pay a hundred euros for, and the difference is almost never skill — it is doing the right things in the right order. Reach for a chemical drain cleaner first and you have made every later step more dangerous. Reach for the plunger without blocking the overflow and it cannot work at all. This guide runs the steps the way a plumber would: work out what kind of blockage it is, try the two cheapest fixes, then open the trap, which is where most kitchen blockages actually live. It also tells you plainly where the line is — the point where continuing yourself costs more than calling someone.
What you'll be able to do: In four short sessions, learn to diagnose and clear a blocked sink with basic tools — and to recognise the blockages that are not yours to fix.
Outcome: "I know whether this is my sink's problem or the whole drain's problem."
Run the taps in every other sink, the bath and the shower for thirty seconds each. What happens elsewhere tells you more than the blocked sink does.
Before touching anything, answer one question: is this one fitting or the whole system? If only this sink drains slowly and everything else is fine, the blockage is in that sink's own pipework — the plughole, the trap or the short run behind it — and it is yours to fix. If the bath gurgles when you empty the sink, if several fittings are slow, or if water comes up in a different one, the blockage is further down the shared drain and nothing you do at this sink will reach it. That is a plumber's job, and continuing can push the problem somewhere worse. The second question is what kind of sink. Kitchen blockages are almost always grease, which cools in the pipe and then catches everything else passing through. Bathroom blockages are almost always hair bound with soap, usually within the first few centimetres of the plughole. Same symptom, different cause, different fix — and knowing which you have saves you from the two hours most people waste trying the wrong one.
Kitchen sink drains but takes a minute, and there is a faint smell. Bath, shower and basin all run away normally. That is a local grease blockage building up in the trap, and it is fixable in this guide. Second case: the bathroom basin is slow, and when it does empty the shower tray fills slightly and gurgles. Two fittings responding to one another means the blockage is in the shared waste pipe past both of them. Nothing at the basin will touch it, and plunging hard could force water back into the shower instead. That one gets a phone call, not a plunger. Thirty seconds of running other taps was the whole diagnosis.
Outcome: "I have tried the two cheapest fixes properly, not half-heartedly."
Find the small hole near the top rim of your sink. That is the overflow, and it is the reason most people's plunging does nothing.
Two fixes cost nothing and clear a good share of blockages, but both are usually done wrong. Hot water and washing-up liquid works on grease and only on grease: a good squirt of detergent down the plughole, left five minutes, then a kettle of hot but not boiling water poured slowly. Not boiling, because boiling water can soften plastic waste pipes and crack a porcelain sink. Repeat it twice before deciding it failed. Plunging works on anything, but only if you get a seal — and a sink has a second opening most people forget. That small hole near the rim is the overflow, and it is connected to the same pipe, so every push you make escapes through it. Block the overflow with a wet cloth held firmly, put enough water in the sink to cover the plunger cup, and work with short sharp pushes — twenty of them, not three. The pull is what shifts the blockage as much as the push. And the one rule with no exceptions: if chemical drain cleaner has already gone down there, do not plunge, because you will splash caustic liquid into your own face.
Kitchen sink, slow for a week. First attempt: plunger over the plughole, four hard pushes, water sloshes about and nothing changes. The overflow is wide open the whole time, so most of the pressure is going up and out of it rather than down the pipe. Second attempt, done properly: detergent down the plughole, left five minutes, a kettle of hot water poured slowly. Still slow. Then a folded wet tea towel pressed hard over the overflow by one hand, the sink filled with about five centimetres of water, plunger seated flat over the plughole to cover it completely, and twenty short sharp strokes — pulling as deliberately as pushing. On the fifteenth the water drops away with a distinct gulp. Total time, including the failed first attempt, about twelve minutes.
Outcome: "I can take the trap off, clean it and put it back without a leak."
Open the cupboard under your sink and find the U-shaped or bottle-shaped piece of pipe. That is the trap, and it is almost certainly where your blockage is.
The trap is the bend under the plughole. It holds a little water permanently, and that water is the seal that stops drain smells coming back into the room. It is also the lowest point in the pipe, which is why grease, food and hair collect there — and why opening it clears most kitchen blockages outright. On modern plastic pipework it comes apart by hand: two threaded rings, unscrewed anticlockwise. Older metal traps may need a wrench and are more fragile. Three things separate a twenty-minute job from a flooded cupboard. Put a bucket underneath first — the trap is full of water by design and all of it is coming out. Clear everything out of the cupboard before you start, so nothing you own is sitting in the splash zone. And check the rubber washers when you reassemble: they must be seated flat and the right way round, because a washer pinched at an angle is the single commonest cause of the slow drip that appears a day later.
Bucket in, cupboard emptied, old towel down. Both rings unscrewed by hand — top first, then bottom — and the U-bend lifts out. Half a litre of grey water into the bucket, followed by the blockage: a grey-white plug of hardened fat the size of a walnut, with coffee grounds and a lemon pip set into it. The trap is scraped out with an old toothbrush, rinsed in a second bucket rather than in the sink above it, and refitted, washers checked, by hand only. Then the test that matters: taps run for a full minute with a dry hand held under each joint. Bucket stays overnight anyway — that is how you catch a slow drip.
Outcome: "I can use a drain snake on the pipe beyond the trap, and I know the point where I stop."
Measure the distance from your sink to the nearest outside wall. That is roughly how far your own pipework runs, and roughly how far you can reach.
If the trap was clean, the blockage is in the pipe beyond it — the horizontal run heading for the main drain. A drain snake (or hand auger) is a flexible coil you feed in and crank. Two rules make it work rather than make things worse: feed it in with the trap removed so you go straight into the waste pipe rather than fighting round the bend, and when you meet resistance, crank and pull back repeatedly rather than shoving. You are trying to hook the blockage and drag it out, not ram it further down where it becomes someone else's problem and a bigger bill. For a bathroom basin, a cheap plastic hair-grabber strip does the same job better, because bathroom blockages sit within the first few centimetres. The stopping points are the important part of this chapter. Call a plumber if more than one fitting is affected, if the snake meets a hard stop that will not move, if water backs up elsewhere while you work, if there is a sewage smell, or if you have already spent an hour. A blockage you force deeper costs more to clear than the one you started with.
Bathroom basin, still slow after the trap came out clean. Hair-grabber strip down the plughole, twisted, pulled: a matted rope of hair and soap the length of a finger. Sink drains instantly, for about two euros, and the snake was never needed. Second case, kitchen: trap clean, snake cranking freely for a metre, then a solid stop that will not shift — and at the same moment the washing machine's outlet starts backing up. Two signals at once mean the blockage is in the shared run past both fittings, so the snake goes away and the phone comes out.
Outcome: "I have a routine that stops the same blockage coming back."
Look at what you pour down your kitchen sink after cooking tonight. That single habit is the cause of most repeat blockages.
Blockages are built, not suffered. The kitchen rule is one sentence: fat, oil and grease do not go down the sink, in any quantity, ever — not even hot and runny, because they cool a metre down the pipe and set there. Pour them into an old jar and bin it once it is full. The same goes for coffee grounds, rice, pasta and anything starchy, all of which swell. In the bathroom, a plughole strainer costing a euro or two catches hair before it ever reaches the trap, and emptying it weekly is the entire maintenance routine. Once a month, run the hot tap hard for a minute in each sink to flush the film that builds on the pipe walls. And treat a slow drain as an early warning, not as a minor annoyance: a sink that takes twice as long as it used to is a blockage half-formed, and dealing with it now is a plunger, while dealing with it in a month is a bucket and a trap.
A household that had blocked the kitchen sink twice in eighteen months changes exactly two habits. An empty jam jar lives under the sink; roasting-tin fat, the oil from a pan, and the grease skimmed off a stock all go into it, and the jar goes in the bin when it is full — about once a month. Coffee grounds go into the food waste instead of down the plughole. Nothing else changes: no chemicals, no monthly ritual beyond running the hot tap hard for a minute on the first of the month. Two years later the sink has not blocked again. The instructive part is what was tried before that did not work — a bottle of caustic drain cleaner every few weeks, which cleared each blockage slowly, damaged the trap seal, and did nothing at all about the fat still going down the plughole every Sunday.
The complete guide — all 5 chapters, every checklist and exercise — as a clean, printable PDF. No email required.
Every guide on this site is produced with the Self-Directed Learning Framework: instead of an article that explains a topic at you, the framework turns it into a structure you work through — each chapter with one outcome, a starting action under twelve minutes, the minimum you actually need to know, a worked example, a checklist, and exercises. It starts from three questions:
Topic: Clearing a blocked kitchen or bathroom sink.
Outcome wanted: Diagnose the blockage, clear it with a plunger or by opening the trap, and know when to stop — within four days.
Starting point: Has never opened a trap, owns a plunger, and currently calls someone when a sink blocks.
The prompt framework behind it is public: see the C.R.A.F.T. prompt framework, including the exact prompt that generated this library.
The other small repair most people pay someone else for, and shouldn't — same idea, twenty minutes and two tools.
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