Blocked sinks are a common household problem that can range from a minor inconvenience to a major hassle. Whether it’s in your kitchen or bathroom, a clogged sink disrupts daily routines and can lead to unpleasant odours and even water damage if not addressed promptly. As experts in drainage with a team of highly skilled drainage engineers at PM247, we aim to provide you with a comprehensive overview of how to unblock a sink. Starting from the most basic methods and moving towards more advanced strategies, this guide will equip you with the knowledge to handle any blockage. We’ll also explore the various causes of blocked sinks and provide tips for prevention based on our extensive experience in property maintenance.

how to unblock a sink

Table of Contents

  1. Understanding the Causes of a Blocked Sink
  2. Basic Tools and Supplies
  3. Step-by-Step Guide to Unblocking a Sink
    • Method 1: Boiling Water
    • Method 2: Baking Soda and Vinegar
    • Method 3: Plunger
    • Method 4: Drain Snake
  4. Advanced Methods
    • Chemical Drain Cleaners
    • Removing and Cleaning the P-Trap
    • Using a Wet/Dry Vacuum
  5. Additional Tips for Dealing with a Blocked Sink
  6. Preventing Future Blockages
  7. When to Call a Professional
  8. Conclusion


Understanding the Causes of a Blocked Sink

Blocked sinks can be caused by a variety of factors, including:

  • Grease and Oil: In kitchen sinks, grease and oil can solidify and cling to the pipes, trapping food particles and other debris.
  • Food Scraps: Food particles that don’t get washed away can accumulate in the pipes.
  • Hair: In bathroom sinks, hair is a common culprit. It can tangle and mix with soap scum, creating a blockage.
  • Soap Scum: Soap residue can build up over time, particularly in areas with hard water.
  • Foreign Objects: Sometimes, small items like jewellery, bottle caps, or toys can accidentally find their way into the sink.


Basic Tools and Supplies You’ll Need To Fix A Sink

Before you start unblocking your sink, gather the following tools and supplies:

  • Plunger
  • Baking soda
  • Vinegar
  • Boiling water
  • Drain snake (also known as a plumber’s snake or auger)
  • Bucket
  • Rubber gloves
  • Old toothbrush or pipe brush
  • Wet/dry vacuum (optional)
  • Chemical drain cleaner (optional)


Step-by-Step Guide to Unblocking a Sink

Method 1: Boiling Water

  1. Boil Water: Bring a kettle or pot of water to a rolling boil.
  2. Pour Slowly: Carefully pour the boiling water directly into the drain. Pour it in stages, allowing it to work through the clog.
  3. Repeat if Necessary: If the water drains slowly, repeat the process two or three times.

Method 2: Baking Soda and Vinegar

  1. Remove Standing Water: If there is standing water in the sink, remove it using a cup or bowl.
  2. Add Baking Soda: Pour about a cup of baking soda into the drain.
  3. Add Vinegar: Follow with a cup of vinegar. The mixture will fizz and bubble.
  4. Wait: Let the mixture sit for 15-30 minutes.
  5. Flush with Boiling Water: Pour boiling water down the drain to flush away the loosened debris.

Method 3: Plunger

  1. Fill with Water: If the sink is empty, fill it with enough water to cover the plunger’s cup.
  2. Position the Plunger: Place the plunger over the drain, ensuring a good seal.
  3. Plunge: Push and pull the plunger vigorously for 20-30 seconds.
  4. Check Drainage: Remove the plunger and see if the water drains. Repeat if necessary.

Method 4: Drain Snake

  1. Insert Snake: Insert the drain snake into the drain until you feel resistance.
  2. Rotate and Push: Rotate the handle and push the snake further into the pipe to break up the clog.
  3. Remove Debris: Pull the snake out and remove any debris attached to it.
  4. Flush with Water: Run hot water to flush the remaining debris.


Advanced Methods to Unblock a Sink

Chemical Drain Cleaners: Sink Unblockers

Chemical drain cleaners can be effective but should be used with caution due to their harsh nature.

  1. Read Instructions: Follow the manufacturer’s instructions carefully.
  2. Pour Cleaner: Pour the recommended amount into the drain.
  3. Wait: Allow the cleaner to sit for the specified time.
  4. Flush: Flush the drain with water, preferably hot, to clear the dissolved debris.

Removing and Cleaning the P-Trap

The P-trap is the curved pipe under the sink that can collect debris.

p-trap unblocking sink

  1. Place a Bucket: Place a bucket under the P-trap to catch any water or debris.
  2. Remove the P-Trap: Use a wrench to loosen the slip nuts and remove the P-trap.
  3. Clean the P-Trap: Clean the P-trap with an old toothbrush or pipe brush.
  4. Reassemble: Reattach the P-trap and tighten the slip nuts.

Using a Wet/Dry Vacuum

  1. Set to Vacuum Liquids: Set your wet/dry vacuum to the liquid setting.
  2. Create a Seal: Cover the drain with the vacuum hose and create a tight seal.
  3. Turn on Vacuum: Turn on the vacuum to suck out the clog.
  4. Check Results: Run water to see if the clog is cleared.


Additional Tips for Dealing with a Blocked Sink

Tips for Using Tools More Effectively

Plunger Tips:

  • Warm Up the Plunger: Soak the rubber end of the plunger in hot water for a few minutes to soften it. This creates a better seal around the drain.
  • Double Plunging: If the blockage is severe, use a plunger on both the sink and the overflow hole simultaneously (if applicable) to increase pressure and suction.

Enhancing Baking Soda and Vinegar Reaction:

  • Cover the Drain: After pouring baking soda and vinegar into the drain, cover the drain with a plug or cloth to keep the fizzy reaction concentrated in the pipe, increasing its effectiveness.

Auger Techniques:

  • Use a Hand-Cranked Drain Snake: For stubborn clogs, a hand-cranked auger can provide more control and force compared to a standard drain snake.
  • Feel for Resistance: As you turn the auger, pay attention to resistance. This often indicates that you’ve reached the blockage. Continue rotating to break it up

Combining Methods:

  • Plunger and Snake Combo: Alternate between using a plunger and a drain snake. Start with the plunger to dislodge the clog and follow up with the snake to remove it.
  • Chemical Cleaners Post-Snake: After using a drain snake, if the clog is partially cleared, a chemical drain cleaner can be more effective in clearing the remaining debris.

Using a Wire Coat Hanger:

  • DIY Snake: If you don’t have a drain snake, straighten a wire coat hanger, leaving a small hook on the end. Use it to fish out debris manually from the drain.

Water Pressure:

  • Garden Hose: If possible, insert a garden hose into the drain and seal the area around it with rags or tape. Turn on the hose to use water pressure to push the blockage through the pipes.

Using Wet/Dry Vacuum More Effectively:

  • Create a Tight Seal: Ensure a tight seal between the vacuum hose and the drain. You can use a wet cloth to improve the seal.
  • Blow and Suck: Many wet/dry vacuums have a blower function. Alternate between sucking the clog out and blowing air into the drain to dislodge the blockage.

Hot Water and Dish Soap:

  • Hot Water and Soap: Pour a generous amount of dish soap into the drain followed by a pot of boiling water. The soap can help break down greasy clogs, and the hot water can flush it away.

Inspect the Garbage Disposal:

  • Reset and Clear: If your kitchen sink has a garbage disposal, ensure it’s not jammed. Use the reset button typically located at the bottom of the disposal unit. Manually turn the disposal blades using an Allen wrench (inserted into the bottom of the unit) to clear any jams.

Using Commercial Enzyme Cleaners:

  • Enzyme-Based Cleaners: Unlike harsh chemicals, enzyme-based drain cleaners use natural enzymes to break down organic material. These are particularly effective for blockages caused by grease and food particles.


Preventing Future Sink Blockages

  • Avoid Pouring Grease: Never pour grease or oil down the drain. Dispose of it in the rubbish.
  • Use a Drain Cover: Install a drain cover to catch food particles and hair.
  • Regular Cleaning: Periodically flush your drains with hot water and use baking soda and vinegar to keep them clear.
  • Dispose of Food Scraps Properly: Scrape food scraps into the rubbish or compost, not the sink.


When to Call a Professional Drainage Specialist

If you’ve tried all the above methods and your sink is still blocked, it’s time to call a professional drainage specialist. Persistent or severe blockages may indicate a more serious issue, such as:

  • Tree Roots: Roots from trees can infiltrate and block pipes.
  • Collapsed Pipes: Old or damaged pipes may collapse and cause blockages.
  • Severe Grease Build-up: Industrial strength grease build-up may require professional cleaning.


Fed up Trying to Unblock Your Sink?

Unblocking a sink can often be a straightforward task if you know the right methods and have the right tools. Starting with simple solutions like boiling water and baking soda and vinegar can often resolve minor clogs. For more stubborn blockages, a plunger or drain snake may be necessary. In some cases, advanced methods such as using a wet/dry vacuum or cleaning the P-trap may be required. By understanding the causes of blocked sinks and taking preventative measures, you can reduce the likelihood of future clogs. But these techniques do not always work and sometimes you will need to call in the professionals, particularly if the issue

At PM247, our team of highly skilled drainage engineers is always ready to assist if you encounter persistent or severe blockages. Remember, if all else fails, don’t hesitate to call a professional drainage specialist. Our experts are equipped with the knowledge and tools to handle even the most challenging drainage issues, ensuring your sink is back to working order in no time.

Call us on 0808 250 4203 or fill in the form here to get your sink unblocked by a skilled PM247 drainage specialist (UK wide service – Top rated on Trust Pilot). 


You might also enjoy reading: