Slow draining sink or bath

Free DIY guide — no sign-up required. Written by a qualified Gas Safe engineer.
DIY Friendly💷 £0£3015–30 min

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Most likely cause & what to check

1

Remove and clean the drain cover — hair and soap build-up is the most common cause.

2

Pour boiling water down the drain in three stages.

3

Try baking soda and white vinegar: pour half a cup of each, cover, wait 20 minutes, flush with hot water.

4

Use a plunger firmly 10–15 times.

5

For persistent blockages, use a flexible drain snake.

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