Possible Reasons Your Bathroom Sink’s Draining Slowly

The bathroom sink is a fixture in your bathroom that you use every day. You wash your hands in it after using the toilet, brush your teeth in it, and expect everything to go down the drain.

If you notice your sink is draining slowly, it’s time to take action. There could be a problem with your plumbing, and you don’t want to wait until it becomes a bigger issue. Bring in professional help to check things out and avoid costly repairs down the line.

Slowly draining sinks can be caused by a few different things. Check out this list of potential reasons your bathroom sink’s taking too long to drain.


Hair can clog up your bathroom sink and make it drain more slowly. To avoid this, try to keep hair out of the drain and clean it regularly. Facial hair, like shaving cream and beard trimmings, can easily clog up a bathroom sink. Make sure to wipe the hair out of the sink before rinsing it. 

P-Trap Blockage

The p-trap is a section of the drainpipe under the sink shaped like a U. This area prevents sewer gas from coming up through the sink by creating a water barrier. However, the p-trap can also collect debris washed down the bathroom sink. 

You will find a clean-out plug at the bottom of this trap that you can use to clear away minor blockages. However, if there is a more significant blockage, you should contact a residential plumber for help. The plumber can disconnect the entire p-trap pipe system, flush it out with a hose, and put it back together to ensure that your bathroom sink works properly again.

Sewer Lines

Your sewer line is responsible for carrying wastewater away from your home. If the pipes deteriorate, they can collapse and cause a blockage. Sludge may also accumulate and slow down the drainage of water. If you’re having sewer line issues, it’s best to contact a professional plumber.

Soap Scum

Soap scum is a common reason for a sink to drain slowly. It is a film that builds up on surfaces in contact with soap and water. Over time, the soap scum will become thicker and will start to slow down the drainage of water. The soap scum is also very sticky, which can attract other dirt and debris to join the blockage. 

Hot water can help to break down the soap scum and clear a slow-draining sink. Simply fill a kettle with hot water and slowly pour it down the drain. Doing this is important as soap scum can build up on the inside of plumbing pipes, causing a significant problem over time.

Tree Roots

The pipes that carry water to and from your sink are called supply lines. These pipes travel through your home and connect to an outside drain or septic system. If there are any leaks in your underground pipes, trees may be attracted to the water and grow into the space. Tree roots can slowly damage pipes, so it is essential to know where they are located in relation to any lines. If tree roots damage pipes, they can be costly to repair.


There are several possible explanations for why a bathroom sink might drain slowly. It could be due to any of the reasons above. If the problem persists, it is best to call a plumber to investigate and resolve the issue.

Do you need an emergency plumber? Turn to Bromac, always ready to offer plumbing and heating solutions and willing to go above and beyond to serve our customers. Call now!

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