Blocked drains are one of the most common plumbing issues London homeowners face. From slow-draining sinks to completely blocked toilets, understanding the causes and solutions can save you time and money.

Common Signs of a Blocked Drain

Water draining slowly from sinks, baths, or showers
Gurgling sounds from pipes or plugholes
Unpleasant odours from drains
Water backing up when using other appliances
Overflowing toilets or outside drains

What Causes Blocked Drains?

Kitchen Drains

Fats, oils, and grease (FOG): Solidify in pipes causing blockages
Food waste: Despite having a disposal, some foods cause problems
Soap scum: Builds up over time, especially in hard water areas

Bathroom Drains

Hair: The number one cause of bathroom blockages
Soap and product buildup: Creates sticky residue
Cotton buds and wipes: Should never be flushed

External Drains

Tree roots: Infiltrate and block underground pipes
Leaves and debris: Accumulate in drain covers
Structural damage: Collapsed or cracked pipes
Fat buildup: From kitchen waste over years

DIY Solutions for Minor Blockages

1. Boiling Water

Pour a kettle of boiling water directly down the drain. This can dissolve minor grease buildups.

2. Baking Soda and Vinegar

Pour half a cup of baking soda followed by half a cup of white vinegar. Wait 30 minutes, then flush with hot water.

3. Plunger

Use a plunger with good suction. Cover overflow holes for better pressure.

4. Drain Snake

A basic drain snake can dislodge blockages in accessible pipes.

5. Enzyme Cleaners

Monthly use of enzyme-based cleaners helps prevent buildups.

When to Call a Professional

DIY methods have limits. Call a professional plumber if:

The blockage won't clear after multiple attempts
Multiple drains are affected simultaneously
You notice sewage backing up
There are gurgling sounds throughout the property
Bad smells persist after clearing
You suspect tree root damage
The drain is collapsed or damaged

Professional Drain Clearing Methods

High-Pressure Jetting: Water jets at 3,000-4,000 PSI clear even stubborn blockages and clean pipe walls.

CCTV Drain Surveys: Camera inspection identifies the exact location and cause of blockages.

Mechanical Rodding: Traditional method effective for solid blockages.

Drain Excavation: For severely damaged or collapsed drains.

Preventing Future Blockages

Install drain guards on all plugholes
Never pour fat down the drain (dispose in bins)
Use cold water when running the disposal
Regular cleaning with enzyme products
Professional inspection annually for older properties

Drain Unblocking Costs in London

Simple sink unblocking: £80-£150
Toilet unblocking: £80-£150
External drain clearing: £100-£200
High-pressure jetting: £150-£300
CCTV survey: £150-£350

Contact Aza & Sons for Drain Emergencies

For fast, effective drain unblocking across London, call Aza & Sons on 07955014805. We offer same-day service with no callout fees for straightforward jobs.

Blocked Drain in London? Causes, DIY Fixes & When to Call a Plumber