What Causes Blocked Drains?

Blocked drains are a common household problem that can lead to unpleasant odours, slow drainage, and even significant water damage if not addressed promptly. Understanding the causes of blocked drains is essential for preventing these issues and ensuring that your plumbing system remains in good working order. In this blog, we’ll explore the most common causes of blocked drains, how to prevent them, and what to do if you encounter a blockage.

Common Causes of Blocked Drains

1. Grease, Fat, and Oil

One of the most frequent causes of blocked drains is the accumulation of grease, fat, and oil. These substances are often poured down the kitchen sink after cooking, where they can solidify and adhere to the inside of pipes. Over time, this build-up narrows the diameter of the pipes, leading to slow drainage and eventually complete blockages.

• How It Happens: When hot grease or oil is poured down the drain, it may initially seem like it will flow away easily. However, as it cools, the grease solidifies and sticks to the pipe walls. This creates a sticky residue that attracts other debris, gradually forming a large blockage, commonly known as a “fatberg.”
• Prevention: To prevent grease-related blockages, avoid pouring cooking fats, oils, or grease down the sink. Instead, allow them to cool and solidify, then dispose of them in the rubbish bin. You can also use a grease trap to capture any residual fats before they enter your plumbing system.

2. Hair

Hair is another common culprit when it comes to blocked drains, particularly in showers, baths, and bathroom sinks. When hair goes down the drain, it can quickly accumulate, especially when combined with soap scum and other debris.

• How It Happens: As hair washes down the drain, it can become tangled and form clumps. These clumps stick to the pipe walls, creating a blockage that can lead to slow drainage or complete obstruction.
• Prevention: To prevent hair from causing blockages, use a drain cover or hair catcher in your shower and sink drains. Regularly clean the cover to remove any accumulated hair before it has a chance to enter the pipes.

3. Foreign Objects

Flushing foreign objects down the toilet or washing them down the sink is a leading cause of blocked drains. Items such as baby wipes, feminine hygiene products, cotton swabs, and even small toys can get stuck in the pipes and cause serious blockages.

• How It Happens: Unlike toilet paper, many of these items do not break down easily in water. When flushed, they can become lodged in the pipes, trapping other debris and leading to a blockage.
• Prevention: To prevent blockages caused by foreign objects, only flush toilet paper and human waste down the toilet. Dispose of other items, such as wipes and sanitary products, in the rubbish bin. In the kitchen, avoid washing food scraps, coffee grounds, and other non-biodegradable items down the sink.

4. Food Waste

Food waste, including leftovers, vegetable peelings, and coffee grounds, can cause significant blockages in kitchen drains. While it may be tempting to wash these items down the sink, they can accumulate in the pipes and lead to serious plumbing issues.

• How It Happens: As food waste decomposes, it can stick to the pipe walls and create a blockage. This is particularly true for starchy foods like rice and pasta, which can expand when wet and cause further obstruction.
• Prevention: To prevent blockages caused by food waste, scrape leftovers into the rubbish bin or compost heap before washing dishes. Avoid putting food scraps down the sink, even if you have a garbage disposal unit, as these can still lead to build-up and blockages.

5. Leaves and Outdoor Debris

Leaves, twigs, dirt, and other outdoor debris can easily find their way into outdoor drains and gutters, particularly during storms or heavy winds. If these drains are not properly maintained, the debris can build up and cause blockages.

• How It Happens: Outdoor drains are designed to handle rainwater, but when they become blocked with leaves and debris, the water can’t flow freely. This can lead to pooling water, slow drainage, and in some cases, flooding.
• Prevention: Regularly clean your outdoor drains and gutters, especially during autumn when leaves are falling. Installing drain covers can also help prevent debris from entering the drains in the first place.

6. Soap and Toothpaste

Excess soap, shampoo, and toothpaste can contribute to blocked drains, particularly in bathrooms. These substances can combine with other debris, such as hair, to form a sticky paste that blocks pipes.

• How It Happens: When soap and toothpaste are washed down the drain, they can solidify and stick to the pipe walls. Over time, this build-up can narrow the pipes and lead to blockages.
• Prevention: Use only the necessary amount of soap, shampoo, and toothpaste, and avoid washing large quantities down the drain at once. Regularly clean your drains to remove any build-up before it causes a blockage.

7. Tree Roots

Tree roots can cause significant damage to your plumbing system by growing into the pipes and causing blockages. This is a particular problem for older homes with clay or concrete pipes, which are more susceptible to root intrusion.

• How It Happens: Tree roots are naturally attracted to the moisture in your pipes. They can enter through small cracks or joints in the pipes and grow inside, eventually causing a blockage or even breaking the pipe.
• Prevention: To prevent tree root blockages, avoid planting trees too close to your home’s plumbing system. If you suspect tree roots are causing a blockage, contact a professional plumber to assess the situation and recommend the best course of action.

8. Poor Installation

Incorrectly installed or damaged pipes can lead to chronic drain issues, including blockages. Poor installation can cause pipes to sag, leading to water and debris accumulating in low spots, eventually causing a blockage.

• How It Happens: If pipes are not properly aligned or if there are issues with the slope of the pipes, water and debris can’t flow freely. This can lead to repeated blockages and ongoing drainage problems.
• Prevention: Ensure that any plumbing work is carried out by a licensed professional to avoid issues with poor installation. Regular inspections can also help identify any potential problems before they cause a blockage.

Conclusion

Blocked drains can be caused by a variety of factors, from the build-up of grease and hair to the intrusion of tree roots and foreign objects. Understanding the common causes of blocked drains can help you take proactive steps to prevent them and maintain a healthy plumbing system. Regular maintenance, such as cleaning drains and using covers, can go a long way in preventing blockages. However, if you do encounter a blockage that you can’t clear yourself, it’s always best to call in a professional plumber to assess and fix the problem.

Experiencing blocked drains in your home? Contact our expert plumbers today for fast and effective drain-clearing services. We’ll help you get your plumbing system back to normal in no time.

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Frequently Asked Questions

1. What should I do if my drain is blocked?

If you have a blocked drain, start by trying to clear it with a plunger or drain snake. If that doesn’t work, it’s best to call a professional plumber to assess the situation and clear the blockage.

2. Can blocked drains cause long-term damage?

Yes, if left untreated, blocked drains can cause long-term damage to your plumbing system, including burst pipes, water damage, and even structural issues in your home.

3. How can I prevent blocked drains in the future?

Prevent blocked drains by being mindful of what you wash down the sink or flush down the toilet. Avoid pouring grease, fat, and oil down the sink, use drain covers to catch hair and debris, and regularly clean your drains.