Clearing a blocked sink

Summary: Learn how to unblock a sink drain, unblocking a kitchen sink, unblocking a bathroom sink and unblocking a shower or bath plug hole.

Over time, your sink, shower or bath can become blocked up, preventing water from flowing through the waste pipe. In bathrooms, this is often caused by hair. In kitchen sinks the cause of the blockage is usually fat or food particles. Over time these debris usually get blocked in the trap (the ‘U’ bend in the piping).

Unblocking the sink drain

  • Check that the cause of the blockage isn’t just hair or gunk covering the plug hole. Once you have ascertained that the blockage is in the pipeline, you will require a sink plunger or a pump-action un-blocker.
  • Block the overflow holes so that when you plunge, the air pressure is not lost through the hole. Fill the bath, shower or sink to a level above that of the rubber part of the plunger.
  • Place the plunger over the plug hole and push up and down quickly. This will force water down the pipe which should have enough force to unblock whatever is causing the blockage.
  • Remove the plunger and see if the water is flowing down the hole as normal. Run the taps for a few minutes just to remove the last of the gunk blocking the pipe.
  • If the blockage hasn’t been unblocked, you will need to remove as much of the water out of the sink as possible. Under the sink is a ‘U’ bend, position a bucket under the ‘U’ bend and unscrew the pipe. Water and dirt will spill out, have a look to see if the blockage is being caused by the ‘U’ bend.
  • Push some wire or a drain snake down the pipe gently, the drain snake should unclog any debris causing the blockage.
  • If the problem is not being caused in the ‘U’ bend, then you may need to check to see if the drain is blocked. Do this by checking the closest drain cover to the blocked sink. If the drain is blocked you will require a set of drain rods to unblock it. See how to unblock a drain.

Prevent future blockages

  • In order to prevent blockages, do not allow food to fall down the plug hole. This can be achieved by purchasing a sieve that sits on top of the plug hole and collects larger particles of dirt.
  • In showers and baths, remove hair when it starts to collect around the plug hole. Leaving it too long will cause blockage problems.

Clearing a blocked sink video

Summary: DIY video showing you how to unblock a bathroom or kitchen sink.

It is not uncommon for a bathroom sink or kitchen sink to become blocked. Many blockages can be cleared with a plunger, so try this first. If that doesn’t work you’ll need to check the P-trap.

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