The short answer

Clearing a blocked drain follows the same order, whatever the cause. Start with a plunger or drain rods for anything near the surface. Move to high-pressure jetting when rodding will not shift it, or when the pipe needs a proper clean. Then bring in a CCTV survey if the same blockage keeps coming back. Where you live in North London changes the method very little. It changes how often you need it, because the age and layout of the drains differ. If the basics fail, send the online enquiry form.

The method ladder, in order

Most blocked drains respond to one of five methods, so try them roughly in this order:

A plunger. Use a good water seal and firm, steady strokes. It suits one slow or blocked fixture, such as a sink, bath or toilet.
Drain rods. Work them by hand through an access point or gully. They reach blockages that a plunger cannot, especially in outside drains.
Chemical cleaners. These are best avoided. They rarely shift solid blockages or roots, and the next person to handle the pipe meets the chemical residue.
High-pressure water jetting. It clears the full bore of the pipe, not just a hole through the blockage. It is the usual professional method when rodding has not finished the job. Our guide to methods to unblock clogged drains compares them in more detail.
A CCTV drain survey. Use it when a blockage returns after clearing. It shows whether a structural fault sits behind the repeat.

Each step exists because the one before it has a limit. Jetting a simple slow sink is overkill. Equally, a plunger is a waste of time on a blockage that keeps returning.

Where the blockage sits changes the approach

“Blocked drain” covers several different problems, and the location tells you what to try:

Sink and basin blockages are usually fat, soap and hair near the trap. A plunger or a short rodding through the waste normally works.
Toilet blockages need a flanged plunger, which seals better against the pan, or a toilet auger. Never add more water to a full pan. Our guide to unblocking a toilet without a plumber shows the steps.
Outside gully blockages are often just leaves and silt on the grate. Clearing the grate solves many calls before any rodding is needed.
Main-run blockages show up as several fixtures backing up together, or gurgling when another drain is used. No indoor DIY step reaches them. Read blocked drain pipe: branch or main run to learn the signs.

Why North London sees so many blockages

The method does not change from postcode to postcode. However, how often you need it does. Much of Enfield, Barnet, Wembley, Edgware, Harrow and Finchley grew through the Victorian, interwar and post-war years. Older streets often have salt-glazed clay drains, and two things make those pipes prone to blocking:

London clay subsoil shrinks and swells with the seasons. That puts steady stress on rigid buried pipes, and it can open up joints. Roots and debris catch at joints.
Mature street trees send roots towards the moisture inside a drain. They enter through any gap a shifted joint leaves. Once inside, they widen the crack and trap whatever flows past.

Many Victorian terraces also share drainage between neighbours. A blockage in one house can therefore come from a shared section, not from your own pipework. Our article on why drains block so often in North London goes into each cause, and what older clay drains need in Edgware gives a local example. Who pays depends on where the pipe sits, so see who is responsible for blocked drains outside.

Prevention that makes a difference

Clay pipework will always need some attention. Even so, because small habits add up, four habits cut how often you need to clear a drain:

Keep fat, oil and grease out of the kitchen drain. They set hard as they cool, and they are a common cause of sink blockages.
Bin wipes instead of flushing them. Even wipes labelled “flushable” do not break down like toilet paper.
Clear outside gully grates often. Do it most in autumn, when leaf fall is heaviest.
Book a drain survey if blockages return. A root or joint problem caught early is a far smaller job than a collapse. Our article on what changes the price of a CCTV drain survey explains the costs, and collapsed drain repair and the no-dig fix explains what a failed pipe needs.

If you want to plan ahead, read how often you should have your drains cleaned. For a sewer pipe, see how to unblock a blocked sewer pipe.

Where we work

Our drain clearance page covers the full service, while we also cover drain unblocking in Enfield, blocked drains in Barnet and drain clearance in Edgware. For outside gullies and boundary drains, see our blocked drains page.

Frequently asked questions

What is the fastest way to clear a blocked drain? For one slow fixture, a plunger is usually fastest. If a plunger and drain rods fail, jetting clears the whole pipe in one pass. As a result, it is the standard professional method for anything beyond a simple surface blockage.

Do drain-clearing chemicals work? Rarely, because they do little against roots, scale or a real obstruction, and nothing against a displaced joint. A plunger or drain rods are more effective and safer for whoever handles the pipe next.

Why do drains in North London block more than in other areas? It comes down to the age and layout of the pipework, not how people use their homes. For example, older clay drains sit in subsoil that moves, often near mature trees whose roots find any shifted joint.