Why is my sink not draining?

Dealing with a kitchen sink that isn’t draining properly can be incredibly frustrating. Whether your sink is draining slowly or has completely stopped, it’s a common household issue. The good news is that most sink blockages can be easily addressed with some basic DIY methods. In this guide, we’ll explore common causes of blocked drains and offer solutions you can try yourself. If you’ve tried everything and your sink is still stubbornly blocked, we’ll also let you know when it’s time to call in the professionals.

One of the most common culprits behind a blocked sink is grease. Over time, cooking oils, fats and grease build up in your pipes, solidifying and blocking the flow of water. When these substances cool, they harden, creating a barrier that slows or completely halts the drainage. Avoid pouring grease or oil directly down the drain; instead, collect it in a container and dispose of it properly once it’s full.

Soap scum is another frequent cause of clogged drains, particularly in sinks where soap is frequently used. When soap interacts with the minerals in your water, it forms a sticky residue that sticks to the walls of your pipes. This can build up over time and reduce water flow, leading to blockages. Regular cleaning and maintenance can help minimise soap scum build-up.

Food remnants like coffee grounds, pasta, rice and small scraps often end up in the kitchen sink. While it’s easy to let these bits wash down the drain, they can accumulate and cause a blockage. Food particles, especially when combined with grease and soap, create a thick, sticky sludge that blocks your pipes. Using a drain cover is a simple solution to prevent food debris from going down the sink.

To fix a blocked sink, start by pouring boiling water down the drain to loosen grease or soap residue. If that doesn't work, try using baking soda and vinegar. Pour the baking soda into the drain, followed by vinegar, and let it bubble for 10 minutes. Then, flush the drain with hot water. If the blockage remains, use a plunger to apply pressure, sealing the drain and pumping up and down. If necessary, check the U-bend under the sink, clean it and reassemble it. For stubborn clogs, a pipe snake can be used to dislodge deeper blockages.

If the blockage persists after trying these methods, it may be time to hire a professional plumber, especially if you notice odours, leaks or water damage. While most blockages can be fixed with DIY methods, a plumber can address more complex issues.