The water in the sink is sitting two inches deep and going nowhere, and under the counter is a bottle of something bright blue that promises to dissolve the problem in fifteen minutes. It will not. It will sit on top of the clog generating heat, soften the trap it is sitting in, and still be there tomorrow — except now there is a cup of caustic liquid in the pipe that has to come out before anyone can work on it safely.
First, which drain is it
This decides everything that follows.
- One fixture slow, everything else fine — the clog is local, in the trap or just past it. Nearly always fixable in twenty minutes.
- Several fixtures slow on the same floor — the branch line is blocked. Harder, but still a plunger-and-snake job.
- Everything slow, or the lowest drain in the house backing up — the main line. Stop. This is a plumber, and continuing to run water makes it worse.
- Gurgling in a different fixture when you drain one — air is finding its way through a partial blockage further down. Treat it as a branch or main problem, not a local one.
Bathroom sink and tub: it is hair, and it is right there
Ninety percent of bathroom clogs are a mat of hair and soap scum within six inches of the opening. You do not need a snake. You need to physically remove it.
- Take the stopper out. Some lift straight out. Others turn a quarter and lift. On older sinks there is a pivot rod behind the drain under the sink — unscrew the retaining nut, pull the rod back, and the stopper comes free.
- Use a barbed drain tool — a flat plastic strip with teeth, two dollars at any hardware store. Push it in, twist, pull slowly. What comes out will be genuinely unpleasant.
- Repeat until it comes back clean.
- Flush with very hot water for a full minute to move the softened scum along.
If that does not do it, the clog is in the trap, and the trap comes apart by hand.
Taking the trap apart
This looks intimidating and is the single most useful plumbing skill a homeowner can have.
- Put a bucket under the U-shaped pipe. It is full of water and will all come out.
- Loosen the two slip nuts by hand — they are plastic on most modern sinks and are meant to be hand-tight. Channel-lock pliers if they resist, gently.
- The U-bend comes off. Empty it into the bucket, not the sink.
- Clean it out with a bottle brush.
- Check the washers are seated correctly, then hand-tighten both nuts back on. Do not use tools to tighten plastic — that is how they crack.
- Run water and watch the joints for a full minute.
If the trap was clean, the clog is past it, in the wall. That is when a snake comes out.
Kitchen sink: grease, and it behaves differently
A kitchen clog is usually congealed fat coating the inside of the pipe, slowly narrowing it over months. Hair tools do nothing here.
What works, in order:
- Boiling water, poured in stages. A kettle at a time, waiting between pours. This alone clears a lot of early grease clogs. Do not do this if you have PVC pipes and a full standing sink — boiling water sitting against a plastic joint can soften it. Drain what you can first.
- Baking soda and vinegar — half a cup of soda, then a cup of vinegar, plug the drain, wait thirty minutes, flush with boiling water. Modest but real, and it will not hurt anything.
- Plunger, covered below.
- Enzyme cleaner overnight. This is the one bottled product worth owning: bacteria that eat grease and organic matter. Slow — it needs eight hours — and completely harmless to pipes. Good monthly maintenance, poor emergency fix.
If there is a garbage disposal, check it first. Run it. If it hums without turning, something is jammed: cut the power at the breaker, then use the hex key that came with it in the slot underneath to turn the blades free by hand.
Plunging, done properly
Most people plunge wrong and conclude plunging does not work.
- Use the right one. A flat-bottom cup plunger is for sinks and tubs. The one with a soft flange that folds out is for toilets. They are not interchangeable.
- Block the overflow. Bathroom sinks and tubs have a second opening — the small hole near the top, or the plate under the tub spout. If it is open, you are pushing air out of it instead of pressure down the pipe. Hold a wet rag over it firmly. This is the step that makes the difference.
- Double sink? Block the other side the same way, hard, or the pressure just goes sideways.
- Water in the basin. Enough to cover the cup. Plunging air accomplishes nothing — water transmits the force.
- Push and pull. The pull is what dislodges things. Fifteen to twenty strokes, then break the seal and check.
The snake
A 25-foot hand auger costs around twenty dollars and handles anything a household drain will throw at you.
Feed it in until it stops, then tighten the thumbscrew and crank. You are either boring through the clog or hooking it. When the resistance gives, keep cranking a few turns, then pull back slowly while still turning — fast makes you drop whatever you caught.
Run hot water afterward to carry off what you broke up.
What keeps it from happening again
- A hair catcher on every bathroom drain. Three dollars, and it eliminates the problem entirely rather than managing it.
- Grease goes in the trash, in a can, not down the sink with hot water. Hot water only moves it further along before it cools and sticks.
- Enzyme cleaner once a month in the kitchen drain, overnight.
- Run water in rarely-used drains — the guest bathroom, the basement floor drain. The trap holds water that blocks sewer gas, and when it evaporates the smell comes up. A cup of water once a month fixes it.
