What causes bathroom sinks to clog?

What causes bathroom sinks to clog

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Used drain openers, DIY cleaning hacks, plungers and everything under the sun? Well it is time to understand the science behind what causes bathroom sinks to clog.

nlike your dish washing sink in the kitchen there is not much that gets into the bathroom sink apart from water. Then how does the sink get clogged every now and then? Well, there is more to that than what meets the eye.

So let’s get into this and see what you may be doing wrong.

Clogged sinks in bathrooms are caused by what

Understanding bathroom sinks

It is important to understand how the bathroom sinks work, they have a different plumbing system than most sinks. This is because some bathroom sinks are more stylish and they require plumbing in a smaller area as compared to a kitchen one or the one in any other place of the house. 

Due to space constraints the size and shape of the sink as well its pipes will vary. Some sinks have a cabinet under them making the pipes even more congested.

In other areas the sink may have little pipe space in terms of height (specially true for sink that look like they are floating) and hence the pipe can be curved and twisted in many places not visible to the eye. A lot of times the buildup of gunk starts off at these curved areas. This slows the drainage process and a lot of thicker debris can form.


What kind of debris builds up in the bathrooms?

The anatomy of a sink drain can vary in every house or washroom. It is always a good idea to have a physical plumbing map around you to know what is going on.If you do not have it that is alright too. This is because the drain will more or less be a combination of curved and straight pipes flowing to the main hole. You will need a tad bit of drain opener to open any clogged drain, usually a plunger will not help. 

However, if you have already done this a couple of times and the drain still does not open then it is time to reevaluate the situation and see what is actually going on there. This is a long-term strategy rather than putting band aid fixes.

As the weather gets hot or you start using radiators the problem gets worse. The heat dries the mixture and makes it harder to dissolve. Similarly during icy seasons the pipes can start to become icy if not properly insulated. The weather can worsen your clogged sink situation.

But, what is really stuck in there? Here’s everything possible and most of these things we normally just ignore.

sink drain

Product build up

You may remove the gunk from your hands, face or skin but the mixture of soapy water, serums, oils and multiple cleansers going down the bathroom sink can get stuck in the drain.

At times we mindlessly drain our remaining face masks or hair dyes and thicker materials like conditioners from rinse in basin hair days into the drain.

The sink drain unlike the shower drain is not as flat or straight and this in addition to particles like dust, insects can together clog your toilet. 

Product of bathroom

Hair fall and other drainable fall out

Anything that goes down the drain, we let it. This means whenever a bowl of pasta will fall in your sink you will let it get in rather than collecting it and putting it in the trash can instead. Now no pasta bowl really falls in the bathroom sink, but things such as hair strands, mud, excessive toothpaste, handwash, fur, pet hair and other solids do go down the drain. 

It is always more difficult to scoop them out and toss them in the bin especially when we are so lazy to put back lids on used toothpaste or the zip on cotton swabs. But, these things may be piling up, drying as they pile up and compounding over time forming hard to remove units of garbage right inside your drain.

Drinking and Health problems 

If you are puking down your bathroom sink a lot then you are in for trouble. Vomit contains solid particles and acids. These acids may hold their own in the sink and cause smell, particles and debris. 

Although it is hard to remember, you should know that whatever you are throwing up, no matter how sick or drunk you are, the vomit belongs in the flush and not in the small opening of the bathroom sink. It will clog and probably not so far away down the drain, in corners and crevices near the top.

Creams and lotions

Like skin care products your body related goodies may be clogging your bathroom. The reason why it is important to notice this is because this happens almost unknowingly.

The creams are usually oil based. So when you rinse your hands or face with a soapy material they can leave your body, but then in the drain the oils drain slower than the thin viscosity of soapy water. 

The slow drainage allows more cold water to flow from top making the materials harder to drain out properly. Another common issue is that a lot of creams are really just plastic. Which when drained in a sink will get stuck onto the walls of the drain and get trapped in the internal pipework making it smell bad and rot. 

Shaving in the sink

If you are guilty of this sin then know that you are in for trouble obviously. The shaving foam, gels, aftershave lotions and the hard hair themselves make for a thick tale that will eventually become a big goop of gunk in your drain.

This really causes the sink to clog. If you are used to trimming in the sink then remember to wipe rather than since the material. You can simply use a washcloth or reusable tissue to clean the sink and wipe the materials out rather than into the drain. 


Too much washing

If you use a lot of washing liquids, detergents, bathroom cleaners and other materials to make your bathroom fancy looking shiny then you may notice a clog. Too much washing can really clog a toilet sink because the materials get little water to be properly diluted and drained.

The material rather becomes a paste overtime and collects into the pipes. The more you use the thicker the paste becomes, eventually trapping even more solids from whatever travels in the pipes such as insects and hair. 

Cement and other materials

If you are not aware then pipes do break, they get cuts, nicks and crevices that then need to be refilled, opened and checked up after a couple of years.

The gunk in the pipes may be from the walls rather than any outside source. So the material clogging the bathroom sink can be really inside the sink rather than coming from the top of the sink. 

In order to check this you can open a drainage pipe in an exposed area of the house, preferably the kind that is straight. When you do you can then hit a torch light to see if there is mudd, breakage or any sort of wall drip. This will give you the idea regarding your bathroom situation. 

If the pipes in the rest of your house are getting damaged, then chances are that the pesky ones in your bathroom are too. This could be the reason why your sinks become self clogged even if you rarely use it. 


If you have tried to prevent it all from happening and you are aware that none of this is happening in your bathroom then perhaps it is time to call a professional plumber who can investigate the issue.

At times things like rats and other pests enter the pipes, make home in there and then grow enough to not be able to get out.

This may become even trickier if a small animal dies there and becomes a clogged mess. You will need an expert to look through and investigate if you suspect something like that is going on in your house or the pipes under it.

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