What does it cost to unblock a drain?

A blocked basin, bath or single toilet is often a problem in the waste pipe or trap serving that one fitting. These are usually short, accessible pipes and can be quick to clear by hand or with a small machine.

When several fittings back up at once, or water is rising in a chamber outside, the blockage is in the underground drain. That generally means lifting chambers to find the affected length and working along it from outside, which is a bigger task. Our guide to a blocked outside drain explains how to tell the two apart.

Rods are pushed along the pipe to break through a blockage. They are simple and work well on short runs and soft blockages close to an access point. Jetting uses a high-pressure hose with a nozzle that scours the pipe wall and flushes debris through. It takes more equipment but clears grease, scale and silt that rods would just push aside.

Which one is used depends on the blockage and the pipe. A jetting visit is usually more involved, but it often leaves the pipe properly clean rather than just open. Our high-pressure water jetting page explains the method.

A blockage just beyond the first chamber is easier to reach than one near the boundary or under an extension. The further it is from an access point, the longer it takes to clear, and the more likely it is that a camera is needed to see what is causing it.

Easy-to-lift chamber covers make for a quick start. Covers buried under paving, gravel or soil, or rusted solid in their frames, add time. If there is no chamber at all, access may be through a gully or by removing a toilet, which takes longer again.

One blockage is usually just something that should not have gone down the pipe. The same drain blocking every few weeks or months is different: it normally points to a fault such as roots at a joint, a sunken length that holds waste, or a cracked section. Paying to clear it again and again adds up.

In that situation, a camera survey after clearing shows the cause. Repairing the defect can work out cheaper over time than repeated call-outs. Our guide to drain repair costs explains how repair options are priced.

A few minutes of checking can save time on the day and help you describe the problem clearly.

Until the drain is open, nobody can be sure where the blockage is or what it is made of. A phone quote is based on what you describe; it may change once the job is seen, and a good contractor will tell you before doing anything extra. Ask how the price is worked out and what happens if the blockage turns out to be bigger than expected.

See our drain unblocking page for how we approach a clearance, or get in touch with your postcode and what you are seeing.