Unblocking a kitchen sink

Free DIY guide — no sign-up required. Written by a qualified Gas Safe engineer.
DIY Friendly💷 £0£2015–45 min

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Most likely cause & what to check

1

Start with a plunger — cover the overflow with a damp cloth to create suction, then plunge vigorously 10–15 times.

2

If that doesn't work: put a bucket under the U-bend (the curved pipe under the sink), unscrew the U-bend by hand or with grips, and clear the blockage directly.

3

For a grease blockage, pour a full kettle of boiling water down the drain followed by a cup of bicarbonate of soda and a cup of white vinegar. Leave 20 minutes then flush.

4

If the blockage is deeper, use a drain snake — insert it through the U-bend opening and work it through until you clear the obstruction.

5

To prevent recurrence: fit a sink strainer to catch food debris, and pour boiling water down the drain weekly.

🛠 Tools & materials you may need

Sink plungerBucketU-bend removal tool or adjustable grips
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