How To Unblock A
Sink

A blocked kitchen or bathroom sink can be a nightmare for homeowners, with unpleasant smells, strange gurgling sounds and dirty standing water all causing disruption. If not cleared quickly, blockages can easily escalate to bigger plumbing problems. 

Fortunately, tackling a blocked sink is often easily achieved with a range of household products, from the handy plunger to baking soda or washing powder. Here at VHL, we have used our extensive knowledge and experience in plumbing to create this handy, easy to follow guide to help you get your sink draining normally in no time. In addition, we will also cover what can cause your sink to become blocked and offer some advice on how you can prevent clogs from forming in your sinks. 

From your kitchen sink to your bathroom sink, these tips and DIY methods will help get the water draining normally in the sinks in your home.

Table of Contents

How To Unblock A Bathroom Sink

Bathroom sinks can be easily blocked by a buildup of hair, soap scum, toothpaste and other grooming products, all leaving you with a solid clog that can be tough to clear. Many drain unblockers and bleaches aren’t effective on hair, leaving your sink blockage resistant to many common methods. Thankfully, we have included a number of methods that are effective at unblocking those stubborn bathroom sink blockages. 

How To Unblock A Kitchen Sink

Kitchen sinks are often blocked by grease, fat and food debris that makes its way down the plughole when you are cooking or washing dishes. Weird smells, strange gurgling sounds and slowly draining water is your sinks’ way of telling you that there is a problem. Take a look at some of the methods below if you have a blocked kitchen sink. 

Check The Garbage Disposal

If your kitchen sink has a garbage disposal, it could be the cause of your blockage issues. Usually, turning on the garbage disposal will clear any clog in it, however, if your disposal isn’t working properly, try resetting it to see if that helps clear the problem. 

If your garbage disposal still isn’t working well or you hear a low humming sound then it may be jammed or broken. Before doing any work on your garbage disposal, make sure you disconnect the power to the uni and NEVER stick your hand in the disposal. 

Once it has been rendered safe, you can try and break up the clog in the disposal by turning the blades manually with an Allen Wrench on the hole of the bottom of the disposal and twisting until you feel less resistance. If that still doesn’t work, it might be time to call in professional help. 

Check The Garbage Disposal

Common Causes Of Blocked Sinks

When it comes to a blocked sink, there are three common causes. These include:

  1. Foreign objects causing a blockage – The most common cause of a blocked sink is the one that you can easily avoid. Anything like hair, soap, toothpaste, food, fat & grease and bits of paper or tissue can all cause blockages. 

  2. Poor installation – If your sink is often getting blocked, then it may have been installed poorly. If this is the case then it is unlikely you will be able to fix this issue yourself and will likely need to call in a professional plumber to fix the situation. 

  3. Storms or bad weather – Heavy rain and storms can cause drains to become blocked outside, which will then back-up into your home, causing blockages. Normally, waiting for the storm to pass and for normal flow to return is your only option here. However, if your outdoor drains are blocked, a professional drain unblocker can help. 

How To Unblock A Sink With A Plunger

The easiest way to unblock a sink is often with a trusty plunger. A plunger is used to suck the air out of a pipe before forcing it back in, which can help to dislodge the blockage. While you can use a toilet plunger to try and unblock your sink, a flat-bottomed sink plunger is far more effective. 

Step 1: The first thing you need to do is to remove any debris such as food fragments, hair, and standing water. You want a relatively water-free sink. So, grab a pair of rubber gloves, a cup, and a bucket and scoop the water out.

How To Unblock A Sink With A Plunger

Step 2: Remove the pop-up plug or the drain stopper and give the area a clean. The aim is to remove as much soap scum or debris as possible. Then create an effective seal by blocking the overflow with something like a dishcloth or old towel. It is also a good idea to lay an old towel down on the floor to catch any water. 

Step 3: Next, position the plunger over the plughole and fill the sink with hot water until half full to help create an airtight seal around the drain. Then pump up and down to create suction until the blockage is cleared. You’ll know the blockage is clear when you fill the sink up and it drains quickly. Repeat the process until the water drains freely. 

How To Unblock A Sink Without A Plunger

If trying to unblock your sink with a plunger isn’t working, or you don’t have a plunger, then try one of the following methods. 

It is possible to dissolve blockages in sinks using a range of common kitchen cupboard ingredients, such as white vinegar, baking soda, salt or even Alka Seltzer indigestion tablets.

How To Unblock A Sink With Baking Soda Or Bicarbonate Of Soda And White Vinegar

This low-cost solution to blocked drains uses two ingredients that you should have in your kitchen to clear the blockage and is a natural alternative to using chemical-based drain cleaners. Remove any standing water from the sink with a cup or bowl. 

Pour a cup of baking soda (baking powder) or bicarbonate of soda down the plughole, followed up with a cup of white vinegar. You will hear a lot of fizzing and may even get some froth back up from the plughole. Close the plug and leave it to sit for around an hour. 

How To Unblock A Sink With Baking Soda And White Vinegar

The fizzing action from the chemical reaction is what helps remove the hair and grime that has built up. Let it sit for around an hour before flushing it through with hot water from the tap. If the blockage isn’t completely cleared but does appear to be making progress, repeat the process again. 

How To Clear A Blockage With Baking Soda And Salt

Another effective combination from the kitchen cupboards that can be used to clear blockages is baking soda and salt. Mix half a cup of each together before pouring the mixture down the drain. Follow up with boiling water from the kettle, which should create a chemical reaction that will aggressively fizz, clearing the sink blockage. Leave for about an hour before flushing through with warm water from the tap. 

How To Unblock A Sink With Washing Powder Or Soda Crystals

Another method that can help clear blockages and leave your sink smelling nicer. This method is great at clearing oily blockages, such as chip fat or other greasy substances in your kitchen sink. 

Pour a couple of tablespoons of washing powder down the plughole and then follow up with a kettle’s worth of boiling water. This should clear any grease or grime that has built up. Soda crystals are similarly effective. 

How To Unblock A Sink With Alka Seltzers And White Vinegar

Alka Seltzers are great for mild blockages and nasty smells. Simply add a couple down the sink and then follow up with a cup of white vinegar. Give it a few minutes before running the hot tap to help flush the blockage. 

How To Unclog A Sink With A Wire Coat Hanger

You can make use of a long flexible wire, like a wire coat hanger that has been unwound and straightened, to clear the blockage, especially if it is further down the waste pipe. You can even create a hook on the end to try and grab on to any debris in the pipe. 

Feed it into the drain so that it bends around the pipe and clears the blockage. But be careful not to scratch the pipe or damage any seals around the plughole. Also, try not to push too roughy, as you might accidentally push the clog further down the pipe. 

Try and use the hook to catch the blockage and pull it back up through the pipe if possible. This prevents it from causing issues further down. Once you are confident the blockage is gone, run hot water down the drain to see if it drains normally. 

How To Clear A Blockage With Water Pressure

It is possible to clear the blockage with a hard burst of water down your sink. Take a plastic 2-litre bottle and fill it with warm water. Tip it upside down with the bottle hole over the plughole and then squeeze as hard as you can. The fast, directed flow of water will hopefully clear the blockage.

How To Clear A Blockage With Hot Water

Simple boiling water can be surprisingly effective at clearing certain sink blockages, especially soap scum clogs in bathroom sinks. Boiling water is most effective when there is a slow drain rather than a lot of tepid sitting water. Boil a kettle’s worth of water and pour the water into the sink in three or four waves. 

The results should be fairly quick if it has worked. Run the tap to see if the water is draining normally, if not, try repeating the process. 

Don’t try this method if your drain is attached to PVC pipes, as the boiling water can damage the plastic.

How To Unblock A Sink With Bleach And Hot Water

A combination of bleach and boiling water can be used to clear some clogs but is less effective on others. For example, bleach won’t eat through hair, making it less effective at unblocking bathroom sinks. In addition, bleach isn’t as environmentally friendly as some of the other methods in this guide. 

Similar to when working with any kind of chemicals, it is important that you show caution when using bleach, especially in standing water. Chemical solutions like bleach work better when the water is still draining, removing the risk of any splashing back on you. Always read the instructions on the bottle before using bleach or any other chemical and always wear rubber gloves and try to keep your skin well covered. 

Clear A Clogged Drain With Drain Cleaner

Using a drain unblocker or drain cleaner is a common method to unblock a sink. Drain unblockers sink through standing water without dispersing until it meets the blockage, making it perfect for clogs with standing water. Always follow the instructions on the bottle before using it and leave it to work for the recommended time before flushing it with hot water. 

How To Unblock A U-Bend

If using a plunger and the other methods above doesn’t work, then it is time to get underneath the sink and remove the U-bend, also known as the waste trap. The u-bend is the first bend in the pipe right under the plughole.

For this, you will need:

  • Rubber Gloves

  • A Bucket

  • An Adjustable Spanner/Wrench

  • Old Clothes

  • A Screwdriver

  • Antibacterial Cleaner

  • An Old Towel

How To Unblock A U-Bend
  1. First thing you should do is make sure the water is turned off and clear space under the sink. Put on your old clothes and rubber gloves to protect yourself from any dirty water. 

  2. Next, place an old towel on the floor to prevent water from getting on the floor and then position the bucket under the basin to catch any water that may spill out once you have removed the U-bend. 

  3. Make sure you pay attention to how the U-bend is attached, so you can put everything back together easily when finished. 

  4. There should be a threaded cap on either side of the U-bend, you need to carefully loosen the fittings that connect the U-bend to the basin with a wrench or screwdriver and be prepared for any water to spill out. When the water stops dripping you can continue to completely unscrew and remove it.

  5. Watch out for any additional fittings, like rubber seals or washers, that might be fitted in the U-bend. 

  6. Remove the U-bend and clear the blockage by pushing a piece of flexible wire through the pipe. Ideally, you want to take the u-bend to another sink or an outside area where you can flush it clean with water.

  7. Once you have cleared the blockage, use the antibacterial spray and sponge to clean the u-bend thoroughly, as bacteria have most likely been lurking in there for a while. Then reattach it so it is the same way it was before and make sure it is completely sealed at both ends. Take care to screw the threaded caps on straight and tight.

  8. Turn the water back on and run the tap to see if the water drains away properly.  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. 

How Do I Know If My Shower Drain Is Clogged?

Now that your sink is unblocked and draining again properly, you need to make sure that you continue to take measures to prevent any future clogs or blockages from building up. The best way to prevent your sink from becoming blocked again is to stop certain things from going down the sink drain, such as:

  • Grease and fat

  • Coffee grounds

  • Plastic

  • Eggshells

  • Gum

  • Paper, tissues and food wrappers

  • Fruit and Veg peels & pieces

  • Starchy foods, like pasta or rice

How To Prevent Clogged Sinks

Another good habit for your pipes and drains is to run hot water down the sink after each use to help keep everything clear and to prevent the build-up of grease and dirt. A regular cleaning routine will also prevent dirt and grime from building up in your sink. In addition, adding a drain cover to your sink to catch any debris before they go down the plughole can help prevent blockages. 

Prevention is always easier than unblocking the sink either by yourself or by calling in a plumber. A regular cleaning routine and being vigilant with what goes down the drain can help prevent your sink from becoming blocked. 

When To Call In A Plumber

If the above methods haven’t managed to clear the blockage, then it is likely time to call in the professionals. Here at VHL, our team of plumbers have extensive experience unblocking and unclogging drains, toilets and sinks, in both bathrooms and kitchens, and will be able to help you clear your blockage quickly and efficiently. 

If your sink is clogged and blocked and you are in need of our professional plumbing services then get in touch with us by phone on 020 3918 6405 or Book Online to arrange for a visit and same-day quote.