How to deal with blocked drains in the home

By: Ryan Suckling

Not only are they a cause for frustration when washing up at the kitchen sink or in the bathroom, but if left untreated, it could mean you’re avoiding a fundamental problem in your home’s plumbing system.

Here are some steps to follow and tools to use when dealing with blocked drains as they occur. While these may sort out your drainage problem in the short term, if the blockage is severe enough, you’ll need to contact a professional plumber to get it properly addressed.

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Signs to look out for

While the obvious sign is a drain that won’t run smoothly and quickly overflows, you could spot a bigger problem developing by looking out for some other things.

One of the most unsettling is a foul smell. If you’re passing your kitchen or bathroom and detect a sewage-like smell, that could indicate food waste, toiletries or other debris is lodged in the pipes, causing a blockage. Another sign is gurgling sounds coming from the drain. Both could indicate a problem that needs specialist attention.

Common causes of a blocked drain

Hair and toiletries

Hair accumulating in pipes is a major culprit. Hair from humans and pets can easily find its way past the waste in showers and sinks. Once it gets into the pipes, the hair tangles and then other debris also become trapped in the mass.

In the bathroom, wet wipes and sanitary products are another contributor. Even use of so-called flushable wipes can lead to a blocked toilet because they do not dissolve in the same way that toilet paper does.

Other small items can also find their way down the drain as well. When these become lodged, it causes other materials and debris to clump together.

Food waste

Another cause is food waste. Many people use sink strainers to catch small pieces of food that may find their way to the bottom of the kitchen sink. However, some food waste may still get through and if it doesn’t easily break down can cause issues. Tea leaves and coffee grounds are particularly resistant.

Kitchen sink build-up is also caused by congealed fats and oils. When these substances enter the drain, they can solidify further down and cause other food debris to also become stuck. That’s why it’s never a good idea to pour oils down the sink.

Tree roots

What’s lurking underneath your home also has a part to play. The roots from trees and large shrubs can be a nightmare for your plumbing system, with the ability to break through pipes by working their way into existing cracks or joins, causing major blockages.

“Tree root intrusion is particularly common on cracked PVC (elbow) joints and older earthenware piping.” Plumber Ben Talbot from BPG tells us.

A professional plumber will need to assess the situation to determine the best course of action. In extreme cases, damaged pipes may need to be replaced and trees removed.

The accumulation of leaves, dirt and garden debris can also result in external drain blockages. Ensure your drain is fitted with an intact grill and the surrounding area is regularly cleared of outdoor waste.

Ways to clear blocked drains

Plunger

The plunger is a household staple for clearing clogged toilets and blocked drains. “I recommend having a small plunger handy to clear minor blockages in the kitchen sink, bathroom basin and toilet,” says Talbot.

Although generally effective for small blockages, the plunger is better placed to dislodge a solid mass rather than the build-up of grease and fatty substances.

When applying the rubber seal over the drain, ensure it evenly covers the surrounding surface so that pressure builds when you start pumping.

If the blockage is in a double-basin sink, apply the plunger seal over the drain that isn’t clogged. This forces the water to make its way to the effected side. To create a more effective seal between plunger and drain, pour a cup of hot water into the blocked basin.

Baking soda and vinegar

Instead of rushing to the shops for a drain cleaner mix, you might consider making your own with a couple of household ingredients. Combining baking soda and white vinegar creates an acid-base reaction that steadily expands and can help to dislodge debris.

Start by pouring one cup of baking soda down the drain and letting it sit for a few minutes, then add one cup of vinegar and another cup of hot water to the mix.

Place a plug over the drain to prevent it from spilling out. Wait for the items to react and fizzle for around 10 minutes and finally run some hot water down the drain to clear away the residue.

Wire hanger

Of all the common causes, a build-up of hair is often the easiest to get rid of. When it comes to removing hair from a blocked drain, you might only need gloves and a prying hand to get the unwanted tangle out.

Another common trick is to straighten out a wire coat hanger, keeping one end of it curved, and dropping it into the drain to fork out the hair. You’ll find this is quite effective in the shower.

Drain auger or plumber’s snake

If the sodden mass still won’t budge, consider purchasing a stainless-steel drain auger or plumber’s snake, which act like a drill. Once you feel you’ve reached the blockage, gently rotate the auger to embed it within the clump. This should give you enough grip to tug it out and clear the drain.

These are especially handy for blockages further down the pipe, even past bends in the piping, as the malleable coiled wire allows you to shape the mechanism to fit the pipe. Some even come with a power drill attachment to maximise force should you face a particularly stubborn mass. However, they can also be tricky to use and, if used incorrectly, may damage pipes. So, use one with caution or ideally leave it to an expert.

Drain cleaners

If you’re looking for a drain cleaner product, you’ll find many brands promising a quick fix in various guises, from ‘enzyme pellets’ to ‘root control crystals.’

Broadly, these come in two categories. Caustic drain products commonly use sodium hydroxide and other chemicals to rapidly target blockages. You should be mindful that caustic cleaners can be extremely corrosive and are harmful to the environment. The other kind of cleaners are enzyme based and are slower to act but much safer for the environment.

How effective these products are remains dubious. “Personally, I don’t recommend drain cleaning products, as I’ve never seen them work effectively. Not to mention how harmful they are to humans and the environment.” Talbot tells us.

If you do opt for a drain cleaner product, carefully read the label to see what chemicals it contains. When applying the product, always wear durable gloves and after use, store it safely away from children and pets.

Ensure you don’t combine or mix these with any other cleaning products as it could activate an unwanted reaction.

How to stop drains from getting blocked

To help prevent your kitchen sink from becoming blocked, always use a sink or drain strainer to catch any food waste before it goes down the drain. And remember to regularly place anything caught by the strainer in the bin. Also avoid pouring substances like oils down the sink.

In the bathroom, remove any build-up of hair from the basin, bathtub or shower waste before it moves and lodges further down the pipe and becomes more difficult to reach.

If you have a blockage that is a recurring problem, you’ll need to contact a professional plumber to come out and assess the effected drains.

Last updated December 2021