How to unblock a sink

Dyno Help and Advice
Is your kitchen or bathroom sink blocked? Well, don’t worry. The following easy to follow guide will help you get your sinks draining smoothly
A blocked sink in your kitchen or bathroom can be an inconvenient and often smelly nightmare, leaving you tempted to give an emergency plumber a call. If, however, you want to save yourself a pretty penny, the best sink unblocker is actually a combination of know-how, patience and good old fashioned elbow grease! 
So if you’ve got the elbows and the patience, we’ve got the know-how for you below - including how to unblock a sink without a plunger. But if you do have one handy... 

Unblocking a sink with a plunger 

Unblocking a sink with a plunger is the easiest way to clear a blockage. Here are the tools you’ll need to get the job done: 
  • A plunger (cup-shaped)
  • A limescale cleaning product
  • A sponge
  • Duct tape (or an old dishcloth)
  • A large towel
  • A cup or beaker 

Step 1: Drain the sink of any water 

If the sink is half-filled with water that won’t drain, remove and dispose of the excess water using the cup. The goal is to have a reasonably water-free sink basin so we can get started 

Step 2: Seal the sink overflow 

Wipe the area around the overflow (the hole just under the taps) using the towel or some tissue to remove any moisture. Now seal the overflow using the duct tape, or stuff it with the dishcloth to create an airtight seal.  

Step 3: Cover the floor with a towel 

Lay the towel down on the floor around the foot of the sink basin to catch any water that might spill over the edge. 

Step 4: Clean the plughole 

Unscrew and remove the plughole so you can thoroughly clean it using the limescale remover and sponge. Have a peek down the plughole to see if you can see any obvious blockages that you can remove by hand. 

Once the area is clean, replace the plughole and wipe away any moisture. If you did remove a blockage, try running the taps to see if the sink drains properly.  

Read this article to find out how to get rid of damp, mould and limescale at home 

Step 5: Take the plunge! 

Place the bottom of the plunger over the plughole and press down firmly. Run the taps for a few seconds until you’ve got a couple of inches of lukewarm water around the plungers seal.  

Now, grip the handle of the plunger with both hands and pump it up and down vigorously to create suction. With a bit of luck, you’ll dislodge the blockage and receive a volley of contented gurgling from the grateful sink. If this doesn’t work and the blockage persists, move on to the tips below. 

How to unblock a sink without a plunger 

If the plunger hasn’t done the trick, or if you haven’t managed to get your hands on one, the following DIY tips using common household items are worth giving a try.  

For all of the following tips ensure your sink is free of water so you have unobstructed access to the plughole. You’ll also need to boil a kettle of water to help flush away the blockage.  

1. Bicarbonate of soda (or baking powder) and white vinegar 

The great thing about this solution is that you most likely have both of these items in your kitchen cupboards. Even if you don’t, you can pick both of them up for next to nothing at your local shop.  

All you need to do is pop a couple of teaspoons of bicarbonate of soda down the plughole and chase it with a cup of white vinegar. Leave it for about five minutes and then try flushing the blockage with the hot kettle water.  

2. Washing powder (biological) 

This is very similar to the above method and a great way to clear oily blockages, such as chip fat or other greasy substances that shouldn’t be down the sink. 

Just pop two tablespoons of washing powder down the plughole and immediately chase it with the entire kettle of hot water. This trick can also be carried out using soda crystals instead of the washing powder.  

3. Alka Seltzers and white vinegar 

This is less effective than the above methods, but still worth trying. Just add a couple of tablets (or teaspoons if you have the powder version) down the sink. Then immediately chase it down with a cup of white vinegar. Give it a few minutes to work its magic and then pour down the whole kettle of boiling water.  

4. Use a wire or tool to poke/pull out the blockage 

For this, you’ll need some flexible drain-unblocking wire from your local hardware store, or a DIY alternative, such as net curtain wire or a metal coat hanger. Feed the wire down the plug hole until you encounter resistance from the blockage. Apply careful but gradual pressure until the blockage is successfully dislodged.  

Important tip: Don’t turn the pipe anticlockwise when using these items as you could unscrew the pipe, resulting in a flood. 

5. Use a blast of water 

If you have an empty plastic bottle lying around (2-litre soft drink bottles work best) then you can try using water pressure to clear the blockage. Just fill the bottle with warm water and place the open end down the plughole. At the same time, quickly squeeze the bottle hard to force the water out of the bottle and down the drain. With a bit of luck, the highpressure blast of water will be enough to clear the blockage.  

6. Use a natural drain cleaner 

A natural drain cleaner is very effective against organic matter, such as fat buildups, grease and even hair. Natural drain cleaner is usually enzymatic - which means that it’s kinder to the environment than bleach or other harsher chemicals such as caustic soda.  

7. Bleach and hot water 

We recommend trying this as a last resort as bleach is quite a corrosive substance. You probably don’t need the safety lecture but just in case, please ensure you always wear protective gloves and avoid getting bleach in your eyes or breathing in the fumes. Once you’re sorted with the precautions, pour about a cupful of bleach down the sink and then slowly pour in hot water from the kettle to flush it down. 
And if none of those work...

How to unblock the u-bend 

If none of the above tips have worked then it’s time to roll up your sleeves and take the fight directly to the blockage. If, at this point, you feel nervous about fiddling with your pipes and want to call a plumber then that’s entirely understandable.  

However, we assure you this is a pretty easy job to carry out yourself. You just need to be prepared to get a little wet. A strong stomach helps too, as that blockage is not going to smell very good...  

You’ll need the following items to get the job done: 
  • An adjustable wrench
  • Rubber gloves
  • Antibacterial cleaner
  • Sponge
  • A bucket
  • Towels 

1. Start off with a little preparation 

First of all get yourself changed into some clothes that you don’t mind getting wet. This is going to be a particularly messy job, so don’t do it in your Sunday best and make sure you wear your rubber gloves.  

Next, lay down some towels under the sink to soak up any excess water. Remember to save one of the towels for yourself as a headrest, as you’ll most likely be under the sink for a while. Finally, place the bucket down under the u-bend. 

Trouble in the loo? How to unblock a toilet

2. Remove the u-bend  

Slowly unscrew the threaded caps from each side of the u-bend using your wrench and direct any rush of water into the bucket. If the threaded caps are rigid (due to age) you can use a spray of WD40 or similar lubricant to loosen them. 

Ideally, you want to take the u-bend to another sink or an outside area where you can flush it clean with water. At this point use the antibacterial spray and sponge to clean the u-bend thoroughly, as bacteria has most likely been lurking in there for a while.  

3. Re-attach the u-bend 

Re-attach the u-bend using the wrench and test that you’ve sealed it correctly by running the cold tap slowly. Hopefully, you won’t have any leaks and you can then remove the towels and bucket. If you do notice a leak, try detaching and reattaching the u-bend again. 

4. Test that you’ve cleared the blockage 

Run the cold tap again to see if the sink is draining correctly.  

What to do if your sink is still blocked 

If at this point the sink is still blocked you may need to concede defeat and call in the professionals. Don’t be disheartened though. In most cases, if the above methods haven’t worked then it could be a sign of a deeper issue that needs to be rectified as soon as possible. 

Common causes of blocked sinks 

It’s important to remember that your sink is designed to drain liquids rather than solids. So to avoid future blockages you should resist the temptation to put the following down your plughole: 
  • Tissues (including toilet tissue)
  • Food (even those little bits of carrot or pet food) 
  • Cotton wool and cotton buds
  • Cigarettes and cigarette ash
  • Paper, plastic and cardboard (including straws)
  • Large quantities of fat (such as chip fat) 
Essentially, if it’s not a liquid, it doesn’t belong down your plughole. If you want to keep your drains clean and maintain a healthy drainage system, then prevention is the best cure.
Read our guide on how to easily clean your drains and help you prevent potential blockages in the future. 

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