Kitchens 4 min read Updated 7 June 2026 Trade verified

How to Unblock a Sink Drain — UK Trade Methods

Kitchen sinks block with fat/grease/food. Bathroom sinks block with hair/soap. Both fixes are DIY in 15 minutes.

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Step-by-step method

1. Bucket under the trap

Every sink has a U-bend (P- or S-trap) under it. Slide a bucket under.

2. Unscrew and clean the trap

Hand-loose the two plastic collars. Empty gunk into bin (never down the drain). Scrub trap with hot water and washing-up liquid.

3. If still blocked, snake past the trap

Feed a drain auger (£12) into the pipe leading to the wall. Twist and pull. Usually a hair/grease mat comes out.

4. Preventive maintenance

Monthly: pour a kettle of boiling water down each sink. Every 6 months: bio-enzyme overnight (Bio-Clean, £10).

Frequently asked questions

Does bicarbonate of soda + vinegar work?+

Marginally on light residue. Doesn't clear hair or grease blockages. Trap removal always wins.

Kitchen sink smells even after clearing?+

Grease coating the drain pipe internally. Pour 2L hot (not boiling) water + degreaser weekly. Consider fitting a food strainer basket.

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