Common causes of blocked drains

Why does my sewer pipe keep getting blocked?

Are you wondering what the number one cause of blocked drains is? Clogged pipes are a common household problem and there are actually several culprits that may be to blame.

If your sewer pipe keeps getting blocked, the main causes include food waste, soap residue and hair. Pipes become blocked when materials get stuck in the drain and stop water from flowing through the system.

Let’s take a closer look at all the different reasons why your pipes may be blocked.

Bathroom drains

Blocked shower, bath and toilet drains are extremely common. Bathroom drains are used every day and many materials can cause the pipe system to clog up.

• Hair
• Soap
• Sanitary products
• Wet wipes

Blocked shower and bath drains are usually caused by a build up of hair. A little bit of hair isn’t a big problem but it doesn’t take long for strands to clump together and cause a blockage.

Soap residue flowing down the plughole can also lead to clogged up pipes. Hard water minerals and soap residue can bind together and stop water from flowing freely through the drainage system.

Flushing sanitary products, wet wipes and other toiletries can damage your bathroom pipes. The only things that should be flushed down the toilet are human waste and toilet paper.

Repeatedly flushing wet wipes can block your home’s entire sewage system. A major blockage can be expensive to fix and could cause dirty water to flow back up out of your drains.

Kitchen drains

As well as the bathroom, the kitchen is another place blocked drains are often found.

We can all be guilty of pouring things down the sink that shouldn’t be there. Unfortunately, these kitchen habits can lead to blocked drains and pipe damage.

The main causes of blocked kitchen drains include:

• Food waste
• Coffee grounds
• Cooking oil/grease/fat

Food particles are not meant to be washed down the sink. A few crumbs down the drain after every meal can build up into a big problem for your pipes.

Starchy foods like pasta and potatoes can quickly cause a blockage. Dairy products are another common culprit, as well as rice and flour.

Avoid tipping coffee grounds down the kitchen sink too. While they may be small, coffee grounds can accumulate in the sink’s U-bend.

Fat, oil and grease should also be kept well away from your home’s pipes. Once cooled, these food products can solidify inside the pipes. Hard grease will make your pipes narrower and impact the flow of water down the drain.

Other than water, anything that goes down your kitchen sink has the potential to cause a blockage.

Outdoor drains

Drains outside of the home can also become blocked. If you are experiencing this problem, it may be due to the following:

• Leaves/weeds
• Dirt and debris
• Tree roots

Outside drains can easily clog up over time. Fallen leaves and weeds can obstruct the drain and stop water from flowing away from your home.

It is also not unusual for dirt and other debris to get into an outside drain and cause a blockage.

Tree roots can also damage outside drains. Roots can grow through cracks in pipes and clog up the whole system. This type of damage can be expensive to repair and you will need to hire a professional to fix the problem.

Signs of a blocked drain

Spotting a blocked drain is easy. There are several telltale signs that mean your pipes are not working as they should.

Slow draining

Water should flow freely down a drain. There is likely a blockage somewhere if water is slowly draining away. If your morning shower is starting to resemble a bath, you may have a problem!

Bad smell

Food waste trapped in the pipes will cause a bad smell. Blocked drains have an unpleasant odour that won’t just go away on its own. The longer it takes to clear the blockage, the worse the smell will be.

Gurgling sounds

Do you have noisy pipes? Gurgling sounds are caused by air that has become trapped in the system. This noise is one of the first signs of a problem and can help you to spot a blockage before it gets worse.

Overflowing

In more severe cases, blocked drains can cause sinks and toilets to overflow. This happens when the drain is too blocked for more water to flow through the system. Water and waste need to go somewhere, though, and this can sometimes be backed up into your home.

How common are blocked drains?

Drains can become blocked by a wide variety of materials. Blocked drains are extremely common, especially in bathrooms and kitchens.

Most people will have dealt with a blocked drain at some point. You are more likely to experience this problem if you regularly flush things down the toilet or pour things down the kitchen sink that belong in the bin.

As blocked drains are so common, several solutions are available.

How to unblock a drain

Now you know why your drain is blocked, it’s time to fix the problem. Depending on how bad the blockage is, you may be able to clear it yourself.

We always recommend hiring a professional for best results.

Here are some of the most common DIY fixes for blocked drains:

Hot water

Pouring boiling water down the drain can break up a buildup of debris inside the pipes. This method is most effective for minor kitchen sink blockages.

If you have disposed of grease or fat down the sink, immediately pouring boiling water down the drain can stop a blockage in its tracks.

Unblocking products

There are several drain unclogging products available to buy. These products are specifically formulated to break up hair, soap residue and other waste trapped inside pipes.

Often these products simply need to be poured down the drain and rinsed away after a certain amount of time.

Plunger

Plungers are effective tools when it comes to dealing with a blocked drain. Make sure the plunger forms a tight seal around the drain’s entrance otherwise this method won’t work.

We recommend always having a plunger handy in your bathroom. This simple device can quickly unclog a blocked toilet.

Homemade solutions

You don’t have to use strong chemicals to clear a small blockage. You may be able to fish out the matter with your hands. Remember to wear rubber gloves!

Alternatively, there are several unclogging formulas you can make yourself. Baking soda and vinegar are often used as alternatives to caustic soda and other strong chemicals.

Hiring a professional plumber

If none of your DIY attempts are successful, you will need to hire a professional. Often, an expert tradesperson will be needed if the blockage is deep in the pipes or more damage has been caused.

A plumber will be able to unblock the drains inside your home. They will perform an inspection and will likely use at least one of the following methods:

• Plunger
• Manual/motorised drain rodding
• Manual removal
• Chemical products
• Disassembling pipes to remove blockage at the source

If your outside drains are blocked, you may need to hire a drain specialist to solve the problem.

These tradespeople can perform a CCTV inspection to find exactly where the pipes are clogged. They also have access to more sophisticated equipment that effectively removes sewer obstruction.

Blocked drains within your property boundary are your responsibility. However, if water is not flowing away from your property, it may be up to your local authority, water supplier or sewage network to fix the issue.

Contact a 24 hour drain clearance service if sewage is flooding into your home or your drains are overflowing.

How much does it cost to unblock a drain?

The price for professional drain unblocking depends on the following:

• The type of clearance method needed
• The type of tradesperson needed
• Your location – tradespeople charge varying rates across the UK

Plumbers charge an average hourly rate of £45. To unblock a toilet, you can expect to pay a professional an average of £100.

Drain specialists charge an average of £85 for drain rodding and £185 for drain jetting.

Key takeaways

• Hair, food waste and soap residue are the most common causes of blocked drains
• A blocked drain will make a gurgling sound, smell bad and cause slow draining
• Minor blockages can often be cleared using simple DIY methods
• A plumber or drain specialist will be needed to remove more severe blockages

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