Choose a drainage engineer who tells you the price structure before starting, carries both rods and a jetter, films the drain with a CCTV camera when the cause is not obvious, and shows you that footage before recommending any repair. A good one also tells you honestly when a blockage is in a shared or public pipe that the water company should clear, even though that means less work for them.

Why the choice matters more with drains than most trades

A blocked drain is urgent, messy and underground, which is exactly the combination that lets a poor operator overcharge. You cannot see the pipe, so you are relying entirely on what the engineer tells you. The difference between an honest clearance and an unnecessary excavation can be a very large bill and a dug-up drive.

The good news is that the evidence exists. A camera can show you precisely what is in the pipe, where it is and how serious it is. The whole point of choosing well is to make sure decisions are made on that evidence rather than on a sales pitch. If you want to see how we approach it, our drainage services page sets out what we do and in what order.

The 8 checks before you book

1. They explain how they charge before they set off

Ask on the phone how the visit is charged: is there a call-out fee, is time charged by the hour or the half hour, and what changes in the evening or at weekends. A reputable firm answers this without hesitation. Be wary of “we’ll see when we get there” with nothing firmer, because that leaves you negotiating with a flooded manhole in front of you.

2. They carry the right kit for the job

Different blockages need different tools:

Method	What it is	Best for	Limits
Drain rods	Flexible rods pushed through from an inspection chamber	Simple soft blockages close to an access point	Can punch a hole through a blockage without cleaning the pipe wall
Drain machine (cable)	A motor-driven cable with a cutting head	Stubborn blockages in smaller pipes and internal wastes	Less effective on heavy grease along the whole run
High pressure jetting	Water driven through a nozzle at high pressure	Grease, scale, silt and root mats along a full run	Needs care on old clay or pitch fibre pipes, and should follow a survey where damage is suspected
CCTV camera	A waterproof camera pushed or crawled through the pipe	Finding the cause, the position and the depth of a problem	Diagnostic only, it does not clear anything

An engineer who arrives with only rods can clear a simple blockage. An engineer who can rod, jet and film can tell you why it happened, which is what stops it happening again.

3. They find the cause, not just the blockage

Clearing the water is only half the job. Ask what caused it. Fat and wipes, a displaced joint catching paper, roots through a cracked clay pipe and a sagging section that holds water all look the same from the manhole. If a drain has blocked more than once, the right next step is a camera, not another clearance.

4. They show you evidence before recommending repairs

If you are told the pipe is cracked, collapsed or full of roots, ask to see the footage. A good engineer will point out the defect on screen, tell you how far along the run it is and how deep, and explain what the options are. Roots can often be cut out and a cracked section lined from inside. Excavation should be the answer only where the pipe has lost its shape or its fall, and you should be able to see why.

5. Their survey report is something you can use

A proper CCTV drain survey produces a recording and a written report, not just a verbal opinion. The report should show the pipe route, the distance to each defect, still images and a clear description of what was found. In the UK, defects are usually described using a recognised coding system (the WRc Manual of Sewer Condition Classification), which means another engineer or an insurer can read it and understand it. That matters if you need a second opinion or are making a claim.

6. They are honest about who owns the pipe

In England and Wales, most shared sewers and lateral drains that were connected to the public sewer before 1 July 2011 were transferred to the water companies on 1 October 2011. In plain terms, the pipe that serves only your property and sits within your boundary is normally yours. A pipe shared with neighbours, or the section beyond your boundary, is normally the water company’s to maintain.

A trustworthy engineer will tell you when the problem is in a shared or public section, so you can report it to the water company rather than pay for it. Our guide on who is responsible for clearing a blocked drain explains the boundaries in more detail.

7. They are insured and put guarantees in writing

Drainage work involves lifting covers, working near foundations and occasionally digging. Ask whether they hold public liability insurance and what guarantee applies to the work. Any lining or excavation should come with written terms, not a handshake.

8. They explain what you can do to stop it happening again

The best engineers leave you with practical advice: what not to put down the sink, whether the drain has a defect that will keep catching debris, and whether a repair now will save repeated call-outs later. If they are happy for you to keep paying for clearances without mentioning an underlying fault, that is worth noting.

Red flags that should make you walk away

If you sign a contract for work at your own home, you normally have a 14-day cancellation period under consumer law. A firm that pushes you to waive that for non-urgent work, such as a relining job on a drain that is currently flowing, is putting its interests first.

What a good first visit looks like

1. The engineer asks what is happening and where: which fittings are slow, whether anything is backing up and whether it has happened before.
2. They lift the nearest inspection chambers to find where the water is standing, which narrows down where the blockage is.
3. They clear it with the least aggressive method that will work, usually rods or a machine, then jetting if the pipe is fouled along its length.
4. They run water and check that it flows freely through each chamber.
5. If it has blocked before, or the cause is unclear, they recommend a camera survey and explain why.
6. You get a clear account of what they found and what they did.

For a worked example of what an urgent visit involves, see our guide to emergency drain unblocking in Hertfordshire.

What it costs with Vantage

In normal working hours there is no call-out fee. Drainage work is charged by time: after the first hour, time is charged in half-hour steps, and any lining, parts or materials are quoted before we use them. Evening, weekend and overnight visits are charged at the out-of-hours rates. CCTV drain surveys have their own published rate. Every rate is published on our prices page, so you know what you will pay before we arrive.

Frequently asked questions

Should I get a CCTV survey or just have the drain cleared?

If it is a first blockage with an obvious cause, such as wipes or fat, clearing it is usually enough. If it has blocked before, drains slowly even after clearing, or you are about to buy the property or build over the run, a camera survey is the sensible step. It tells you whether you have a habit problem or a pipe problem.

Can jetting damage an old drain?

Jetting is safe on a sound pipe and is the best way to clean grease and silt from the whole run. On an old clay or pitch fibre pipe that is already cracked or deformed, high pressure can make the damage worse, which is why a good engineer surveys a suspect drain before jetting it hard.

How do I know if the blockage is the water company’s problem?

Lift your inspection chamber covers if it is safe to do so. If your own chamber is full but the next one downstream, especially one outside your boundary or shared with a neighbour, is also full, the blockage may be in a shared or public pipe. Report it to your water company and they will tell you whether it is theirs.

What qualifications should a drainage engineer have?

There is no single compulsory licence for domestic drain clearance, so look at the evidence instead: proper equipment, written reports, insurance, clear pricing and reviews from real customers. Ask how long they have been doing drainage work and whether they carry out the repairs themselves.

Is a drain survey worth it when buying a house?

Usually, yes. A standard home survey only looks into accessible chambers from above and does not test or film the pipes. A camera survey can reveal root ingress, cracked or displaced joints and deformed pitch fibre pipes before you are committed to the purchase.

Drainage help across Hertfordshire, Bedfordshire and Cambridgeshire

If you have a drain that is blocked, slow or keeps coming back, our own engineers can clear it, film it and tell you plainly what they found and who is responsible for it. See our drainage services or call 01462 506374, which is answered 24 hours a day, 7 days a week, with 24/7 emergency cover.