Clearing a slow
sink or shower drain

Bathroom drains block with hair. Kitchen drains block with grease. They are different problems and the fix for one is useless on the other.

Updated July 2026 · 6 min read

Work out which problem you have

	Bathroom	Kitchen
Usual cause	Hair bound with soap scum	Cooking fat and food residue
Where it sits	Within a few inches of the drain	Further along, coating the pipe wall
What works	Physical removal	Heat and detergent, then flushing
Onset	Gradual over months	Gradual, worse in cold weather

Bathroom: pull it out

Shower and bathroom sink clogs are nearly always hair, and nearly always sitting just below the drain opening — well within reach.

1. Remove the drain cover. Usually lifts out, unscrews, or twists off.
2. Use a barbed plastic drain tool. A thin plastic strip with backward-facing barbs, a couple of dollars. Push it in, twist, pull out. It's unpleasant and extremely effective.
3. Repeat until it comes out clean.
4. Flush with hot tap water to clear the residue.

Kitchen: heat, then detergent, then flush

Grease clogs don't sit in one lump. Fat pours down warm, cools, and coats the inside of the pipe, narrowing it gradually. Pulling won't help because there's nothing to grab.

1. Run the hottest tap water you have for two or three minutes to soften the fat.
2. Add a good squirt of dish soap — it's a degreaser, which is the actual mechanism here.
3. Follow with more hot water to carry it away.
4. Repeat. Grease rarely clears in one go.

If that fails, the trap under the sink can be unscrewed by hand or with a wrench. Put a bucket underneath first — it's full of water and whatever else. It's a genuinely easy job on most sinks, and the trap is where things end up.

Why not just use drain cleaner?

Enzyme-based drain maintenance products are a different thing — slow, gentler, and useful as monthly prevention rather than as an emergency fix.

What about baking soda and vinegar?

It fizzes impressively and does very little. The reaction happens instantly at the surface and produces mostly carbon dioxide and water — it has no meaningful power against a hair mass or a grease coating further down. It's a fine deodoriser. It is not a drain clearance method.

When it isn't the fixture

If more than one drain is slow, or water appears in a fixture you didn't use, the problem isn't the sink or the shower — it's the line they share. See what that means. Nothing you do at the fixture will fix a shared-line blockage.

Keeping them clear

• A hair catcher over the shower drain. Two dollars, prevents most bathroom clogs entirely.
• Never pour cooking fat down the sink. Let it set and bin it. Fat is the single biggest cause of kitchen drain problems and of municipal sewer blockages.
• Run hot water for thirty seconds after washing up.
• Clean the pop-up stopper every couple of months.