What Causes Blocked Drains? Everything You Need to Know!

Blocked drains are more than a minor inconvenience, they can lead to costly repairs, foul smells, and damage to your property if left untreated. In fact, the UK spends over £100 million every year dealing with blocked drains. Most of these could have been avoided with a little awareness and regular maintenance. So, what’s really clogging up those drain pipes?

Let’s dive into what causes blocked drains, both inside and outside the property, and what you can do to clear them effectively. By the end, you’ll know exactly how to keep your drainage system flowing smoothly.

What Causes Blocked Drains?

The most common cause of blocked drains are usually right under our noses, or, more accurately, in our homes! Here’s a quick rundown of the major offenders:

1. Grease and Fat: Pouring cooking oil, grease, and fats down the sink is a guaranteed way to create a sticky, stubborn blockage. When hot grease cools, it solidifies inside the pipes, gradually building up and narrowing the drainage path until water can barely flow through. You wouldn’t pour candle wax down the sink, right? Think of grease in the same way.
   
2. Food Waste: We’ve all washed those small bits of food down the sink thinking nothing of it, but, food waste, even in tiny amounts, can easily build up in your pipes. When you combine this with grease, soap and everyday dirt, it can quite quickly build up and lead to a blocked drain. Think of potato peelings, coffee grounds, and eggshells, they’re not going anywhere fast once they hit your drainage system.
   
3. Hair: Hair is one of the biggest offenders when it comes to bathroom blockages. It tangles, knots, and sticks to soap residue, creating a nasty web of gunk that traps more debris as time goes on.
   
4. Soap Scum: You might not think of soap as a problem, but when soap combines with minerals in water, it forms a hard residue called soap scum. This can cling to the insides of your pipes, causing gradual build-ups and reducing water flow.
   
5. Foreign Objects: Kids’ toys, cotton buds, wet wipes, and even sanitary products. Flushing or washing down anything that isn’t meant to go in the drain can cause serious blockages. Some items might get lodged in the pipes, while others absorb water and swell, making the blockage even worse.
   
6. Tree Roots: One of the trickiest causes to deal with. Tree roots naturally seek out water and nutrients, and your drainage pipes are an easy target. They can crack into your pipes, causing obstructions or completely blocking them. Sometimes, removing or dealing with tree roots in your drainage system might be covered by your home insurance. Read our blog post “Are blocked drains covered by home insurance” for more detail.
   

So, what about outside? Let’s look at what causes blocked drains in gardens, driveways, and other external areas.

What Causes Blocked Drains Outside?

Outside drains might seem like they can handle more than indoor plumbing, but that’s not the case. They’re actually more prone to serious blockages. Here are the main reasons why your outside drains might be clogging up:

1. Leaves and Debris: Fallen leaves, twigs, and garden waste can quickly build up and block outside drains, especially during autumn. If left unchecked, they’ll form a dense mat that prevents water from flowing, leading to surface flooding and slow drainage.
   
2. Mud and Silt: Heavy rainfall can wash mud, silt, and small stones into your drainage system. This sediment collects at the bottom of the drain, gradually accumulating until the flow of water is restricted or completely stopped.
   
3. Tree Roots (Again!): Tree roots don’t just target indoor plumbing. They’re a massive problem for outside drains too. Once they invade, they grow quickly, taking up space and breaking through pipes, leading to both blockages and potentially expensive repairs.
   
4. Collapsed Pipes: Outside drains are exposed to more pressure from ground movement, heavy vehicles, and even construction work nearby. This can cause pipes to crack or collapse, creating obstructions that need professional intervention.
   
5. Improper Disposal of Garden Waste: Dumping soil, leaves, or other garden waste directly into outside drains is a recipe for disaster. Drains are designed to handle water, not garden materials, and these items can cause significant blockages over time.
   

What Clears Blocked Drains?

So, you’ve got a blocked drain, now what? Here are a few methods to get things flowing again:

1. Boiling Water: A simple fix for minor blockages caused by grease or soap build-up. Pouring boiling water down the drain can melt away any fatty deposits and loosen up soap scum. If pouring water down a toilet, make sure the water is not boiling as this can crack or damage the toilet.
   
2. Plunger: A plunger isn’t just for toilets! It’s a great tool for sinks and showers too. Position the plunger over the drain, create a tight seal, and plunge up and down a few times to dislodge any clogs. The suction method of the plunger will hopefully loosen any blockages and allow water to flow freely again without any issues.
   
3. Drain Snake: For more stubborn blockages, a drain snake can be inserted into the drain to physically break up and pull out the blockage. It’s especially useful for removing hair or dislodging foreign objects.
   
4. Natural Drain Cleaners: Combine baking soda and vinegar for a natural cleaning solution that fizzes and breaks down minor blockages. Simply pour half a cup of baking soda down the drain, followed by half a cup of vinegar. Let it sit for 15 minutes, then flush with hot water.
   
5. High-Pressure Water Jetting: For serious blockages, high-pressure water jetting is the go-to solution. A powerful stream of water blasts away debris, grease, and even tree roots, leaving your pipes clear and functioning as they should. This method requires professional tools and equipment and we recommend contacting a drain unblocking company to carry out the work.
   
6. CCTV Drain Survey: When you can’t locate the cause of a blockage, a CCTV drain survey can be a game-changer. This involves using a small camera to inspect the inside of your drains and pinpoint the exact location and nature of the obstruction.
   

What to Do If My Drains Are Blocked?

First things first: don’t ignore it. A blocked drain might start as a minor inconvenience, but it can quickly turn into a much bigger problem. Follow these steps:

1. Identify the Cause: Determine whether the blockage is inside or outside, and whether it’s affecting just your property or other areas as well. This will help you figure out who’s responsible for fixing it and what type of solution is needed.
   
2. Try DIY Solutions: If you’re confident the blockage isn’t too severe, try using a plunger, boiling water, or a natural drain cleaner. Remember to avoid harsh chemical drain cleaners, as they can damage your pipes and worsen the problem.
   
3. Call a Professional Drainage Company: If DIY methods don’t work or if the blockage is outside or in a shared drain, call a professional drainage service like Blocked Drains Dorchester. They have the expertise and equipment to handle everything from minor clogs to complete blockages caused by tree roots or collapsed pipes.
   
4. Prevent Future Blockages: Prevention is better (and cheaper) than cure! Avoid pouring grease down the sink, use drain guards to catch hair and food, and clear away leaves and garden waste regularly to keep your outside drains clear.
   

Final Thoughts

Blocked drains aren’t just inconvenient—they can lead to expensive repairs and damage if not dealt with promptly. Understanding what causes blocked drains, both inside and outside, can help you avoid common pitfalls and keep your drainage system in tip-top shape.

If you’re struggling with a blocked drain and need professional help, Blocked Drains Dorchester is just a call away. We’ve got the tools, the expertise, and the experience to clear any blockage—fast! Don’t wait until it’s too late—get your drains sorted today!