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How to unblock a kitchen sink
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How to unblock a kitchen sink

Posted by Adam Chard in Kitchen advice | 3 years ago 7 min read

If the worst comes to the worst and your kitchen sink gets blocked, we’re here to help you out with all our best tips and tricks.

At some point, you are likely to experience a blocked kitchen sink. There can be any number of reasons why this happens, be it due to the piping being clogged with dirt and grime, or as a result of bulky items going down the drain that are best disposed of in the bin.

Whatever the reason, the most important thing is to find a way to unblock the sink as quickly as possible.

If you experience a blocked kitchen sink, there are a number of things you can do to potentially fix the problem. Read on to find out how to unblock a sink.

How does a sink work?

Naturally, you’ll find sinks in both the bathroom and kitchen and, because they serve different functions in the home, they also feature individual components to support this.

The main difference between the two is that kitchen sinks are designed to be connected to various features such as washing machines, dishwashers, water filters and food disposal units. Meanwhile, bathroom sinks will usually just have a tap and a simple drainage system installed. Kitchen sinks will feature a strainer to help with disposal of food and other wastage, while a bathroom sink will usually have a pop-up stopper that prevents it from filling up with water.

While there are only subtle differences between the two, it may be worth checking out our guide to unblocking a bathroom basin if this is the type of sink that is blocked. In this article, we will be focusing solely on kitchen sinks.

Whenever a blockage occurs, the first place many people check is the U-bend (the U-shaped pipe underneath every sink). This is designed to retain a certain portion of water every time the sink is used to prevent sewer gases potentially rising up through the sink drain. On many occasions, this is the area where a blockage occurs and removing the pipe here to clean the area can solve the problem.

However, this isn't always the case. Using the tips below, we offer you some additional solutions to a blocked sink.

Kitchen sinks

Kitchen sinks come in all shapes and sizes and differ from bathroom basins in a few key ways

Why do kitchen sinks get blocked?

A blocked kitchen sink always comes as a surprise and there can be a variety of reasons why it has happened. Some of the most common causes are:

  • Fatbergs—a build-up of grease and fat over time
  • Food scraps—pasta, bread, vegetable peelings, etc.
  • Development of limescale
  • Human hair

By keeping a close eye on what goes down the sink, you stand a better chance of avoiding a sink blockage. Do not dispose of cooking fat down the sink as this can lead to the creation of a fatberg, while limescale can also be managed by pouring hot water followed by baking soda and white vinegar down the sink on occasion, to cleanse the drain.

How to tell if you have a blocked kitchen sink

There will always be warning signs that your kitchen sink is about to become blocked and being aware of these helps you take proactive measures to stop it from occurring. The 3 main signs to look out for are:

Unpleasant smells

If you have bad smells coming from the drain, it is likely a tell-tale sign that food or other items are stuck in the pipes. Running water down the sink to clear it may aggravate the bacteria and make the smell worse.

Slow water drainage

When it takes longer than normal for water to drain from the sink, there could be a block developing—especially if it is not draining at all. If other kitchen appliances are experiencing the same issue, there is a blockage that needs to be cleared.

Gurgling sounds

When the drainage system is struggling to push water through you may hear gurgling sounds created by trapped air. This could be the first warning sign you hear before any of the others start to make themselves known.

These are all clear warning signs that the water system is experiencing an issue that needs to be fixed. The faster you find a solution, the less likely it be that the issue develops into something more costly and inconvenient.

Having to call out a professional plumber in an emergency can be very expensive, added to the fact you will have to take time out of your day for them to visit your home to unblock the sink.

Kitchen taps

Keep things flowing freely in your kitchen with our tips on unblocking a sink

How to unblock a kitchen sink

Before you start to search the internet for a plumber, take a look at the options below to see if you can unblock the sink yourself.

Use a plunger

The obvious go-to choice is to pick up a plunger to see if you can unblock the sink. It works by sucking the air out of the piping below before pushing it back in, aiming to dislodge whatever it is causing the blockage.

Make sure the sink is dry and place the plunger cup over the plughole. Once the seal is formed around the plughole push the handle up and down using a pumping action.

You may hear some gurgling sounds that indicate the blockage is being cleared, or even some items pushed back into the sink. Double check by running some water to see if the problem has been fixed (not too fast, in case it fills up the sink).

Push through the blockage

There are occasions when all it takes is a quick burst of water to break through the blockage.

To try this method, fill up a 1 or 2 litre drink bottle with hot water, stand it upside down on the plughole and give the bottle a hard squeeze to push the water out as quickly as possible.

It’s a basic version of a power flush—a method used by professional plumbers to clean out the pipes in gas heating systems.

Special solutions

Sometimes you need specialist products that can combat the grease and grime that is causing the blockage, as a plunger isn’t able to generate enough force.

There are a number of drain unblocking products available on the market, although they can be quite harsh on the drain and sometimes linger around the sink once finished.

A better alternative may be to use a mixture of baking soda and white vinegar. Use the following method:

  • Pour boiling water down the drain as preparation
  • Prepare one cup of baking soda and one cup of water/white vinegar to pour down the sink
  • You will hear a fizzing sound as the solution gets to work—leave for around 5 minutes
  • Pour boiling water down the drain once more

If the blockage still persists, bleach may be able to help by pouring it down the sink. This is best left to work overnight, before pouring boiling water down the sink in the morning as the final step.

It may also help to use the plunger to dislodge any final bits of gunge or dirt that might still be in place.

Use a plumbing snake

Also referred to as a drain auger, this is a physical tool you can purchase from DIY stores that is designed to physically reach inside piping to resolve the blockage in the U-bend section. Alternatively, you can use a wire coat hanger to reach inside, although be careful about creating scratch marks and piercing holes. Follow these steps:

  • Place a bucket/bowl under the U-bend
  • Unscrew the 2 U-bend sections slowly as water will drain out below
  • Once the water has stopped, remove the U-bend
  • Use the auger/coat hanger to remove anything causing the blockage
  • Apply warm water with dishcloth to clean out pipe

After you have finished, put the U-bend securely back into place. You may need to use plumber’s tape to ensure the pipe is watertight. Keep the bucket/bowl in place and run the tap to ensure there is no water leakage.

If all else fails, it is likely you will have to call out a plumber. Sometimes a professional is needed to use their experience and expertise to resolve the issue. The most important thing is to find a way to fix the blockage that ensures you, and anyone else in your household, can safely use the sink.

Kitchen sink with rinser

Kitchen sinks with separate rinser bowls and filter plugs can help prevent particles from blocking pipework

More fixes for your home

When you encounter issues with plumbing in your home, as you inevitably do from time to time, head to, where you'll find plenty of practical advice. We will help you troubleshoot tap problems, show you how to unblock a toilet and how to replace a cracked tile, amongst many other expert articles. Most issues can be resolved without having to call on a tradesperson, saving you time, money and hassle.

Shop kitchens

If your kitchen sink has seen better days, it may be high time you searched for a replacement. At Victoria Plum, we've used our vast knowledge and expertise in bathrooms to produce a high quality kitchen selection, including a range of stylish sinks, taps, worktops, units and much, much more. To browse, simply click on the image below.

Shop kitchens

Author, Adam Chard

Posted by Adam Chard in Kitchen advice | 3 years ago

A born & raised West Countryman, now living on the Yorkshire Coast, for over 10 years Adam has been bringing home interior ideas to life at Victoria Plum. Adam’s favourite interior styles have been shaped by both urban and natural influences.

Sales Line 0344 264 4141 Track order Design Service Trade account

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