Drain unblocking, drain surveys and relining

On 1 October 2011, private sewers and lateral drains in England and Wales were transferred to the water and sewerage companies. A private sewer here means a pipe shared by two or more properties. A lateral drain is a pipe that serves only your property but lies outside its boundary, for example under the pavement. Both are now the water company's responsibility, including clearing blockages.

What stays with you is the drain that serves only your property and lies within its boundary: the pipes from your sinks, toilet and gutters down to the point where they join a shared pipe or cross the boundary. If you rent, the landlord is normally responsible for keeping drains in repair. Scotland and Northern Ireland have their own arrangements through Scottish Water and NI Water, and properties on a septic tank or cesspool are a separate matter again.

A simple test helps. If only one sink or toilet is slow, the blockage is almost certainly in your own pipework. If your inspection chamber is full but your neighbour's is clear and further downstream, it is probably yours. If the chambers of several houses are backing up, it is likely a shared sewer, and you should report it to the water company before paying anyone.

Source: gov.uk

Most blockages are cleared with rods or with a high-pressure water jetter that breaks up fat, wet wipes, silt and roots. Jetting is quick, but it only removes what is in the pipe. If the pipe itself is cracked, displaced at a joint or has roots growing through it, the blockage tends to come back.

That is where a CCTV drain survey comes in. A camera on a cable or crawler travels through the drain and records its condition. A proper survey report includes the recording, a written description with distances along the pipe, and a sketch or plan of the drain run. Home buyers sometimes order one before exchanging contracts on an older house, particularly where there are large trees near the drains.

Damaged pipes can often be repaired from the inside. Relining inserts a resin-soaked liner that hardens into a new pipe within the old one; patch repairs fix individual defects. Where a pipe has collapsed, excavation may still be the only option.

Blocked drains are often urgent, and urgent jobs are where price disputes start. If you invite a trader to your home for urgent repairs, the usual cooling-off right for contracts agreed at home does not apply to that repair. Agree the call-out charge, the hourly or fixed rate and what counts as extra work before the van arrives, and ask for it in a text or email.

Be wary of a clear-then-survey-then-reline sequence being sold in one visit under pressure. If the drain runs freely after jetting, you can take the survey recording away and decide on repairs later.

• which fittings are affected: one sink, all downstairs drains, the whole house
• whether water is coming up in an inspection chamber, a gully or inside
• whether neighbours have the same problem
• if you know it, where the inspection chambers are and whether you can lift the covers safely
• whether you need clearing only, or a CCTV survey with a written report
• for businesses: kitchen grease traps, opening hours and access

Most household blockages come from a short list of causes: cooking fat and oil poured down the sink, wet wipes and other items flushed down the toilet, and tree roots finding their way into old clay pipes. Chemical drain cleaners rarely shift a solid blockage and can make the drainage company's work more hazardous. Food businesses often have extra duties on grease management that their water company can explain.

Your request is shown, without your name or contact details, to drainage companies covering your postcode, after you confirm your phone number and email address. One company can buy it, and once it does, the request is no longer offered to anyone else. It pays Offrano for the request, while the service costs you nothing.

We email you the company's name, address and phone number before it receives your details. We cannot guarantee that a company picks up every request; unsold requests are withdrawn after 21 days. We check that the buyer is a registered business, not how well it clears drains, so ask about call-out rates, survey reports and guarantees on relining before you agree.