It’s a Monday morning. You’ve just managed to get the kids ready for school, you’re about to jump in the shower, and then you see it: a growing puddle of murky water that refuses to go down the plughole. A blocked drain is more than just an inconvenience; it’s the kind of household drama nobody asks for. The gurgling sounds, the unpleasant smells, and the slow-draining water are all signs of a plumbing villain at work.
Here at BDS Drainage, we’ve seen it all. As London’s trusted emergency drainage company, we understand that when your drains give up, you need a fast and reliable fix. But what if you could prevent the problem in the first place? This guide will expose the most common causes of blocked drains in London homes, explain how to perform a drain blockage fix yourself, and provide practical tips to keep your pipes flowing freely.
The usual suspects: common blocked drain causes UK
Your home’s drainage system works hard, but it isn’t invincible. Most blockages are caused by everyday items that shouldn’t be there. Here are the main culprits we encounter in London homes.
Grease, fat, and oil build up

After cooking a Sunday roast, it’s tempting to pour the leftover fat down the sink. But when hot grease, fat, and oil cool down, they solidify inside your pipes. This creates a sticky trap for other debris, leading to stubborn blockages. Over time, these can contribute to the infamous “fatbergs” that plague London’s sewer system.
To avoid this, collect cooled grease and oil in a container (like an old jar) and dispose of it in your general waste bin. For commercial kitchens, grease traps are essential and often legally required.
Food waste & coffee grounds

Certain food items are notorious for causing drain blockages. Things like rice and pasta expand when they absorb water, clumping together to form a solid mass. Coffee grounds are another problem; they don’t dissolve and can accumulate in pipes, creating a sludgy obstruction.
A simple fix is to use a sink strainer to catch food particles before they enter the drain. Always scrape leftover food from plates into the bin before washing up.
Hair

We all shed hair in the shower, but when it mixes with soap scum and shampoo residue, it can form dense, stubborn clogs in your bathroom drains. It’s one of the most frequent blocked drain causes UK households face.
Placing a drain cover or hair catcher over your plughole is an easy and effective way to prevent this. These devices are inexpensive and can save you a lot of trouble in the long run.
Non-flushable items (baby wipes)

Your toilet is not a bin. Flushing anything other than the “3 P’s” (pee, poo, and paper) can lead to serious blockages in your home’s plumbing and the wider sewer network. Items like wet wipes (even those marked “flushable”), cotton buds, sanitary products, and kitchen roll do not break down in the same way as toilet paper.
Make it a household rule to only flush the 3 P’s. Keep a bin in your bathroom for everything else to avoid a costly and unpleasant blockage.
Tree roots

London’s beautiful old trees have extensive root systems that naturally seek out moisture. If you have older, clay-based pipes, tiny cracks can attract roots, which then grow inside, causing significant blockages and even pipe collapse.
If your property has large trees nearby, it’s wise to be proactive. A professional CCTV drain survey from a company like BDS Drainage can identify root intrusion early, allowing you to address the problem before it leads to major damage.
DIY drain unblocking: when to try it and when to call the pros
For minor clogs, a simple drain blockage fix might be all you need. Before calling for help, you could try these DIY methods:
- Hot water flush: Carefully pour a kettle of boiling water down the drain to dissolve grease and soap scum.
- Baking soda and vinegar: Pour a cup of baking soda down the drain, followed by a cup of vinegar. Let it fizz for 15-30 minutes, then flush with hot water.
- Plunging: A good old-fashioned plunger can often dislodge minor blockages in sinks and toilets.
However, some jobs are best left to the professionals. You should call BDS Drainage if you experience:
- Persistent blockages: If the clog keeps coming back, there might be a more serious underlying issue.
- Foul odours: Nasty smells can indicate trapped waste or a problem with your sewer line.
- Multiple blocked drains: If several drains are blocked at once, it suggests a blockage in the main drain line.
- Slow draining: Consistent slow draining across multiple fixtures is another sign of a deeper problem.
When you’re facing blocked drains in London, our team has the expertise and equipment to diagnose and resolve the issue quickly and efficiently.
Proactive prevention: tips to keep your kitchen and bathroom drains clear
The best way to deal with blocked drains is to prevent them from happening in the first place.
- Regular maintenance: Once a week, flush your internal drains with hot water to keep them clear of buildup. You can also use enzymatic drain cleaners, which use bacteria to break down organic waste without harming your pipes.
- Careful disposal: Be mindful of what goes down your sinks and toilets. Properly dispose of grease, food scraps, and non-flushable items.
- Professional inspections: Schedule a regular CCTV drain survey on your outside drain, especially if you live in an older property or have large trees near your property boundary that could be affecting your external drains. Early detection can save you from costly repairs down the line.
Frequently asked questions
How often should I get my drains cleaned?
We recommend having your drains professionally inspected and cleaned at least once a year. This preventative maintenance helps to avoid major blockages and keeps your drainage system healthy.
Is your work guaranteed?
Yes. At BDS Drainage, all our professional drain unblocking comes with a 100-day guarantee. We stand by the quality of our service, giving you peace of mind that the job is done right.
Do you offer emergency services?
Absolutely. We provide 24/7 emergency drainage services across London. We know that drainage problems don’t stick to a 9-to-5 schedule, so we aim to be at your property within 90 minutes of your call.
What should I do if a pipe bursts?
First, turn off your main water supply by locating and turning the stopcock. This will minimise water damage. Then, call us immediately. We will prioritise your situation and send an engineer to provide a fast and effective solution.
Your trusted partner for blocked drains London
Maintaining clear drains is crucial for a happy, stress-free home. While simple preventative measures can go a long way, sometimes you need an expert. From stubborn fatbergs to invasive tree roots, the most common causes of blocked drains require a professional touch.
Don’t let a blocked drain ruin your day. The BDS Drainage team is on call 24/7 to handle any drainage emergency. With our 100-day guarantee and commitment to customer satisfaction, you can trust us to get your drains flowing freely again.
Contact us today for a free, no-obligation quote and let our experts take care of your blocked drains in London.








































