How to unblock a sink

A blocked sink is a common problem in the home that’s usually caused by a build-up of organic material in your pipes. It can seem like a daunting task but fixing it yourself might be easier than you think.

So, if yours is blocked, get your DIY hat on and try these steps below to get it draining again:

1. Clean your plug

   If you have a thumb plug (the type that you raise and lower with a rod behind the tap) then the first thing to do is pull it out and clean it because there could be a build-up at the base. You can do this by just lifting it out from the plug hole. Clean the plug thoroughly, removing any obvious dirt, and then pop it back into the plughole.

   If this doesn’t work, or if you have a regular plug, move onto step two.

2. Flush the pipes

   If your sink is draining slowly and isn’t completely clogged, you might be able to fix the problem by flushing it.

   Wait for it to drain completely then fill a two-litre bottle with hot water and pour it down the plughole while squeezing it. This might dislodge anything in the pipe that’s preventing the sink from draining normally.

3. Use a plunger

   If the flush didn’t work, or your sink is completely clogged, then it’s time to grab a plunger.

   If the sink is draining but very slowly, put the plug in and fill it halfway. This extra pressure helps to create a better seal over the plughole with the plunger. Next, remove the plug and quickly put the plunger into the water, covering the plughole before working it up and down.

   If the sink won’t drain at all and is full of water, do the same but without filling the sink from the tap.

   If you don’t have a plunger, you can try to cover the plughole with your palm and mimic the suction movements. If the blockage is small this just might work!

4. Use some household items

   If plunging didn’t do the trick, some simple household items might.

   If the plug hole is exposed, pour two teaspoons of bicarbonate of soda, or Alka-Seltzer, down it followed by a cup of white vinegar. You should hear fizzing, which is the chemical reaction of the build-up being broken down and dissolved. After an hour, follow up the white vinegar with a full kettle of boiling water.

   Another option is to use two teaspoons of biological washing powder, followed immediately with a full kettle of boiling water. Washing powder breaks down grease and fat on your clothes, it breaks it down in your pipes, too.

5. Use drain cleaner

   If the household stuff wasn’t strong enough, it’s time to move onto a chemical cleaner. They’re designed to break down organic materials such as food waste or hair and you can buy a bottle at your local supermarket or hardware store.

   Whichever you decided to use, make sure you read the instructions thoroughly and wear rubber gloves and any other protective gear recommended when handling it.No chemical cleaner will break down anything synthetic, so if using one doesn’t work, you could be looking at something other than an organic obstruction.

6. Use drain-unblocking wire

   Drain-unblocking wire is also known as a plumber’s snake? It’s a flexible, thick coil that you can push down directly into the plughole to remove stubborn obstructions. When you’re using it, make sure to twist the wire as it’s going down to help it manoeuvre around the U-Bend.

   Any resistance you feel could be the obstruction, so make sure you work the wire aggressively to remove it. Once the wire moves more freely within the pipe, pour plenty of cold water down the plughole to wash the pipes out and test to see if your sink is now unblocked.

7. Remove the U-Bend

   If none of the above has worked, the next step is to remove the U-Bend. Most modern U-Bends will simply unscrew by hand, so you don’t need to be a DIY pro to do this.

   First, make some room under the sink and put a bucket under the U-Bend before unscrewing it. Use the bucket to catch any of the dirty water that might be released. Once the water is drained, peer down the plughole from above the sink to look for an obstruction. If you can see it, try removing it using the drain-unblocking wire, or a long thin object like a knitting needle. If you can’t see anything, you know that the obstruction is in the U-Bend, so you’ll need to clean the inside of it.

   Once you’ve removed the obstruction, screw the U-Bend back on, keeping the bucket under the sink. Then run some cold water down the plughole to test if the sink is draining properly.

   Remember not to empty the bucket in the same sink you’ve just cleaned!

Still not draining?

If you’ve tried all of the above and your sink is still clogged, it’s time to admit defeat and call in a professional.

Why not fill out the ‘What needs doing?’ field below and we’ll put you in touch with a trusted local tradesperson to properly fix your issue.